From 64f8157108af3a1da7f92d4704e7239e01e0dd80 Mon Sep 17 00:00:00 2001
From: Subham1999 <subhamsantra2016@gmail.com>
Date: Thu, 29 Aug 2024 23:25:43 +0530
Subject: [PATCH 1/5] GRAPH

---
 .idea/workspace.xml                           |  47 ++++--
 .../graph/MostStonesRemovedSameRowCol.java    | 136 ++++++++++++++++++
 2 files changed, 171 insertions(+), 12 deletions(-)
 create mode 100644 src/main/java/com/thealgorithm/graph/MostStonesRemovedSameRowCol.java

diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 92cd1eb..4ec4f0c 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,9 +4,9 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="d1dce324-e0e9-40ed-8855-0f1c77b6fb86" name="Changes" comment="WordSearch.java added">
+    <list default="true" id="d1dce324-e0e9-40ed-8855-0f1c77b6fb86" name="Changes" comment="modified the doc">
+      <change afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/miscellaneous/MostStonesRemovedSameRowCol.java" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/src/main/java/com/thealgorithm/backtracking/PalindromePartitioning.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/backtracking/PalindromePartitioning.java" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -89,7 +89,7 @@
       <recent name="com.subham.ta.graph" />
     </key>
   </component>
-  <component name="RunManager" selected="Application.PalindromePartitioning">
+  <component name="RunManager" selected="Application.MostStonesRemovedSameRowCol">
     <configuration name="CombinationSumII" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
       <option name="MAIN_CLASS_NAME" value="com.thealgorithm.backtracking.CombinationSumII" />
       <module name="TheAlgorithm" />
@@ -103,12 +103,12 @@
         <option name="Make" enabled="true" />
       </method>
     </configuration>
-    <configuration name="PalindromePartitioning" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
-      <option name="MAIN_CLASS_NAME" value="com.thealgorithm.backtracking.PalindromePartitioning" />
+    <configuration name="MostStonesRemovedSameRowCol" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
+      <option name="MAIN_CLASS_NAME" value="com.thealgorithm.miscellaneous.MostStonesRemovedSameRowCol" />
       <module name="TheAlgorithm" />
       <extension name="coverage">
         <pattern>
-          <option name="PATTERN" value="com.thealgorithm.backtracking.*" />
+          <option name="PATTERN" value="com.thealgorithm.miscellaneous.*" />
           <option name="ENABLED" value="true" />
         </pattern>
       </extension>
@@ -116,12 +116,12 @@
         <option name="Make" enabled="true" />
       </method>
     </configuration>
-    <configuration name="PermutationI" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
-      <option name="MAIN_CLASS_NAME" value="com.subham.ta.backtracking.PermutationI" />
+    <configuration name="PalindromePartitioning" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
+      <option name="MAIN_CLASS_NAME" value="com.thealgorithm.backtracking.PalindromePartitioning" />
       <module name="TheAlgorithm" />
       <extension name="coverage">
         <pattern>
-          <option name="PATTERN" value="com.subham.ta.backtracking.*" />
+          <option name="PATTERN" value="com.thealgorithm.backtracking.*" />
           <option name="ENABLED" value="true" />
         </pattern>
       </extension>
@@ -157,11 +157,11 @@
     </configuration>
     <recent_temporary>
       <list>
+        <item itemvalue="Application.MostStonesRemovedSameRowCol" />
         <item itemvalue="Application.PalindromePartitioning" />
         <item itemvalue="Application.WordSearch" />
         <item itemvalue="Application.CombinationSumII" />
         <item itemvalue="Application.SubsetsII" />
-        <item itemvalue="Application.PermutationI" />
       </list>
     </recent_temporary>
   </component>
@@ -374,7 +374,23 @@
       <option name="project" value="LOCAL" />
       <updated>1724742612046</updated>
     </task>
-    <option name="localTasksCounter" value="26" />
+    <task id="LOCAL-00026" summary="modified the doc">
+      <option name="closed" value="true" />
+      <created>1724869859287</created>
+      <option name="number" value="00026" />
+      <option name="presentableId" value="LOCAL-00026" />
+      <option name="project" value="LOCAL" />
+      <updated>1724869859287</updated>
+    </task>
+    <task id="LOCAL-00027" summary="modified the doc">
+      <option name="closed" value="true" />
+      <created>1724869912287</created>
+      <option name="number" value="00027" />
+      <option name="presentableId" value="LOCAL-00027" />
+      <option name="project" value="LOCAL" />
+      <updated>1724869912287</updated>
+    </task>
+    <option name="localTasksCounter" value="28" />
     <servers />
   </component>
   <component name="Vcs.Log.Tabs.Properties">
@@ -403,7 +419,8 @@
     <MESSAGE value="Nothing" />
     <MESSAGE value="CombinationSumII.java added" />
     <MESSAGE value="WordSearch.java added" />
-    <option name="LAST_COMMIT_MESSAGE" value="WordSearch.java added" />
+    <MESSAGE value="modified the doc" />
+    <option name="LAST_COMMIT_MESSAGE" value="modified the doc" />
   </component>
   <component name="XDebuggerManager">
     <breakpoint-manager>
@@ -491,6 +508,12 @@
           <line>71</line>
           <option name="timeStamp" value="41" />
         </line-breakpoint>
+        <line-breakpoint enabled="true" type="java-line">
+          <condition expression="vertex.row == 3 &amp;&amp; vertex.col == 4" language="JAVA" />
+          <url>file://$PROJECT_DIR$/src/main/java/com/thealgorithm/miscellaneous/MostStonesRemovedSameRowCol.java</url>
+          <line>99</line>
+          <option name="timeStamp" value="47" />
+        </line-breakpoint>
         <line-breakpoint enabled="true" type="java-method">
           <url>file://$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/CoursesII.java</url>
           <line>44</line>
diff --git a/src/main/java/com/thealgorithm/graph/MostStonesRemovedSameRowCol.java b/src/main/java/com/thealgorithm/graph/MostStonesRemovedSameRowCol.java
new file mode 100644
index 0000000..284ada7
--- /dev/null
+++ b/src/main/java/com/thealgorithm/graph/MostStonesRemovedSameRowCol.java
@@ -0,0 +1,136 @@
+package com.thealgorithm.graph;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
+
+/**
+ * @author: Subham Santra
+ */
+public class MostStonesRemovedSameRowCol {
+
+  static class Solution {
+    static class Vertex {
+      int row;
+      int col;
+
+      public Vertex(int row, int col) {
+        this.row = row;
+        this.col = col;
+      }
+
+      @Override
+      public boolean equals(Object o) {
+        if (this == o) return true;
+        if (!(o instanceof Vertex vertex)) return false;
+        return row == vertex.row && col == vertex.col;
+      }
+
+      @Override
+      public int hashCode() {
+        return Objects.hash(row, col);
+      }
+
+      @Override
+      public String toString() {
+        return "{" + row + ", " + col + '}';
+      }
+    }
+
+    /**
+     * The intuition is -- As all the vertices will be connected - we will use DFS to find out no of
+     * connected components
+     *
+     * @param stones
+     * @return
+     */
+    public int removeStones(int[][] stones) {
+      Map<Vertex, Set<Vertex>> graph = new HashMap<>();
+      Map<Integer, Set<Vertex>> rowMap = new HashMap<>();
+      Map<Integer, Set<Vertex>> colMap = new HashMap<>();
+
+      for (int[] stone : stones) {
+        Vertex vertex = new Vertex(stone[0], stone[1]);
+        if (rowMap.containsKey(vertex.row)) {
+          for (Vertex sameRowVertex : rowMap.get(vertex.row)) {
+            graph.putIfAbsent(vertex, new HashSet<>());
+            graph.get(vertex).add(sameRowVertex);
+
+            graph.putIfAbsent(sameRowVertex, new HashSet<>());
+            graph.get(sameRowVertex).add(vertex);
+          }
+        }
+        if (colMap.containsKey(vertex.col)) {
+          for (Vertex sameColVertex : colMap.get(vertex.col)) {
+            graph.putIfAbsent(vertex, new HashSet<>());
+            graph.get(vertex).add(sameColVertex);
+
+            graph.putIfAbsent(sameColVertex, new HashSet<>());
+            graph.get(sameColVertex).add(vertex);
+          }
+        }
+
+        rowMap.putIfAbsent(vertex.row, new HashSet<>());
+        colMap.putIfAbsent(vertex.col, new HashSet<>());
+
+        rowMap.get(vertex.row).add(vertex);
+        colMap.get(vertex.col).add(vertex);
+      }
+
+      Set<Vertex> removedVertices = new HashSet<>();
+      int connectedComponents = 0;
+      for (int[] stone : stones) {
+        Vertex vertex = new Vertex(stone[0], stone[1]);
+        if (!removedVertices.contains(vertex)) {
+          ++connectedComponents;
+          DFS(graph, removedVertices, vertex);
+        }
+      }
+
+      return stones.length - connectedComponents;
+    }
+
+    /**
+     * This method will check each vertex and remove it. This will continue to remove all the
+     * connected vertices
+     *
+     * @param graph
+     * @param removedVertices
+     * @param vertex
+     */
+    private void DFS(Map<Vertex, Set<Vertex>> graph, Set<Vertex> removedVertices, Vertex vertex) {
+      if (removedVertices.contains(vertex)) {
+        return;
+      }
+
+      if (!graph.containsKey(vertex)) {
+        return;
+      }
+
+      removedVertices.add(vertex);
+      for (Vertex nextVertex : graph.get(vertex)) {
+        DFS(graph, removedVertices, nextVertex);
+      }
+    }
+  }
+
+  public static void main(String[] args) {
+    System.out.println(
+        new Solution().removeStones(new int[][] {{0, 0}, {0, 1}, {1, 0}, {1, 2}, {2, 1}, {2, 2}}));
+
+    System.out.println(new Solution().removeStones(new int[][] {{0, 1}, {1, 0}, {1, 1}}));
+
+    System.out.println(
+        new Solution().removeStones(new int[][] {{0, 0}, {0, 2}, {1, 1}, {2, 0}, {2, 2}}));
+
+    System.out.println(
+        new Solution()
+            .removeStones(
+                new int[][] {
+                  {0, 0}, {0, 1}, {1, 0}, {1, 1}, {2, 1}, {2, 2}, {3, 2}, {3, 3}, {3, 4}, {4, 3},
+                  {4, 4}
+                }));
+  }
+}

From 543bc300a707d0260f7e22c08f44604b74d432cf Mon Sep 17 00:00:00 2001
From: Subham1999 <subhamsantra2016@gmail.com>
Date: Fri, 30 Aug 2024 21:27:41 +0530
Subject: [PATCH 2/5] LC GRAPH HARD ShortestCycleInGraph

---
 .idea/workspace.xml                           |  37 +++---
 .../graph/ShortestCycleInGraph.java           | 106 ++++++++++++++++++
 2 files changed, 126 insertions(+), 17 deletions(-)
 create mode 100644 src/main/java/com/thealgorithm/graph/ShortestCycleInGraph.java

diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 4ec4f0c..b6f09c1 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,8 +4,8 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="d1dce324-e0e9-40ed-8855-0f1c77b6fb86" name="Changes" comment="modified the doc">
-      <change afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/miscellaneous/MostStonesRemovedSameRowCol.java" afterDir="false" />
+    <list default="true" id="d1dce324-e0e9-40ed-8855-0f1c77b6fb86" name="Changes" comment="GRAPH">
+      <change afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/ShortestCycleInGraph.java" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
@@ -89,7 +89,7 @@
       <recent name="com.subham.ta.graph" />
     </key>
   </component>
-  <component name="RunManager" selected="Application.MostStonesRemovedSameRowCol">
+  <component name="RunManager" selected="Application.ShortestCycleInGraph">
     <configuration name="CombinationSumII" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
       <option name="MAIN_CLASS_NAME" value="com.thealgorithm.backtracking.CombinationSumII" />
       <module name="TheAlgorithm" />
@@ -104,11 +104,11 @@
       </method>
     </configuration>
     <configuration name="MostStonesRemovedSameRowCol" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
-      <option name="MAIN_CLASS_NAME" value="com.thealgorithm.miscellaneous.MostStonesRemovedSameRowCol" />
+      <option name="MAIN_CLASS_NAME" value="com.thealgorithm.graph.MostStonesRemovedSameRowCol" />
       <module name="TheAlgorithm" />
       <extension name="coverage">
         <pattern>
-          <option name="PATTERN" value="com.thealgorithm.miscellaneous.*" />
+          <option name="PATTERN" value="com.thealgorithm.graph.*" />
           <option name="ENABLED" value="true" />
         </pattern>
       </extension>
@@ -129,12 +129,12 @@
         <option name="Make" enabled="true" />
       </method>
     </configuration>
-    <configuration name="SubsetsII" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
-      <option name="MAIN_CLASS_NAME" value="com.subham.ta.backtracking.SubsetsII" />
+    <configuration name="ShortestCycleInGraph" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
+      <option name="MAIN_CLASS_NAME" value="com.thealgorithm.graph.ShortestCycleInGraph" />
       <module name="TheAlgorithm" />
       <extension name="coverage">
         <pattern>
-          <option name="PATTERN" value="com.subham.ta.backtracking.*" />
+          <option name="PATTERN" value="com.thealgorithm.graph.*" />
           <option name="ENABLED" value="true" />
         </pattern>
       </extension>
@@ -157,11 +157,11 @@
     </configuration>
     <recent_temporary>
       <list>
+        <item itemvalue="Application.ShortestCycleInGraph" />
         <item itemvalue="Application.MostStonesRemovedSameRowCol" />
         <item itemvalue="Application.PalindromePartitioning" />
         <item itemvalue="Application.WordSearch" />
         <item itemvalue="Application.CombinationSumII" />
-        <item itemvalue="Application.SubsetsII" />
       </list>
     </recent_temporary>
   </component>
@@ -390,7 +390,15 @@
       <option name="project" value="LOCAL" />
       <updated>1724869912287</updated>
     </task>
-    <option name="localTasksCounter" value="28" />
+    <task id="LOCAL-00028" summary="GRAPH">
+      <option name="closed" value="true" />
+      <created>1724954143566</created>
+      <option name="number" value="00028" />
+      <option name="presentableId" value="LOCAL-00028" />
+      <option name="project" value="LOCAL" />
+      <updated>1724954143566</updated>
+    </task>
+    <option name="localTasksCounter" value="29" />
     <servers />
   </component>
   <component name="Vcs.Log.Tabs.Properties">
@@ -420,7 +428,8 @@
     <MESSAGE value="CombinationSumII.java added" />
     <MESSAGE value="WordSearch.java added" />
     <MESSAGE value="modified the doc" />
-    <option name="LAST_COMMIT_MESSAGE" value="modified the doc" />
+    <MESSAGE value="GRAPH" />
+    <option name="LAST_COMMIT_MESSAGE" value="GRAPH" />
   </component>
   <component name="XDebuggerManager">
     <breakpoint-manager>
@@ -508,12 +517,6 @@
           <line>71</line>
           <option name="timeStamp" value="41" />
         </line-breakpoint>
-        <line-breakpoint enabled="true" type="java-line">
-          <condition expression="vertex.row == 3 &amp;&amp; vertex.col == 4" language="JAVA" />
-          <url>file://$PROJECT_DIR$/src/main/java/com/thealgorithm/miscellaneous/MostStonesRemovedSameRowCol.java</url>
-          <line>99</line>
-          <option name="timeStamp" value="47" />
-        </line-breakpoint>
         <line-breakpoint enabled="true" type="java-method">
           <url>file://$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/CoursesII.java</url>
           <line>44</line>
diff --git a/src/main/java/com/thealgorithm/graph/ShortestCycleInGraph.java b/src/main/java/com/thealgorithm/graph/ShortestCycleInGraph.java
new file mode 100644
index 0000000..30809d4
--- /dev/null
+++ b/src/main/java/com/thealgorithm/graph/ShortestCycleInGraph.java
@@ -0,0 +1,106 @@
+package com.thealgorithm.graph;
+
+import java.util.ArrayDeque;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Queue;
+
+/**
+ * @author: Subham Santra
+ */
+public class ShortestCycleInGraph {
+  public int findShortestCycle(int n, int[][] edges) {
+
+    // Build the Graph DS
+    Map<Integer, List<Integer>> graph = new HashMap<>();
+    for (int[] edge : edges) {
+      graph.putIfAbsent(edge[0], new ArrayList<>());
+      graph.putIfAbsent(edge[1], new ArrayList<>());
+
+      graph.get(edge[0]).add(edge[1]);
+      graph.get(edge[1]).add(edge[0]);
+    }
+
+    // System.out.println(graph);
+
+    // Will do BFS
+    // But we need to know for each node - the shortest cycle that node is part of.
+    return BFS(graph, n);
+  }
+
+  int BFS(Map<Integer, List<Integer>> graph, int n) {
+    int[] shortestCycleCount = new int[n];
+    Arrays.fill(shortestCycleCount, Integer.MAX_VALUE);
+
+    // Will perform breadth first search on all nodes
+    for (int node = 0; node < n; ++node) {
+      int[] time = new int[n];
+      Queue<int[]> queue = new ArrayDeque<>();
+      queue.add(new int[] {node, 0, -1});
+
+      while (!queue.isEmpty()) {
+        int[] _node = queue.poll();
+        int currentNode = _node[0];
+        int visitingTime = _node[1];
+        int parentNode = _node[2];
+
+        // the current node is already visited
+        // that means this is a cycle with 'node'
+        if (time[currentNode] > 0) {
+          shortestCycleCount[node] =
+              Math.min(shortestCycleCount[node], time[currentNode] + visitingTime);
+          continue;
+        }
+
+        // calculate current node's visiting time.
+        // if not first time, then always keep the lowest visiting time from 'node' to 'currentNode'
+        time[currentNode] =
+            (time[currentNode] == 0) ? visitingTime : Math.min(time[currentNode], visitingTime);
+
+        for (int child : graph.getOrDefault(currentNode, Collections.emptyList())) {
+          if (child == parentNode) {
+            continue;
+          }
+
+          queue.add(new int[] {child, visitingTime + 1, currentNode});
+        }
+      }
+    }
+    // System.out.println(Arrays.toString(shortestCycleCount));
+    return Arrays.stream(shortestCycleCount).filter(i -> i != Integer.MAX_VALUE).min().orElse(-1);
+  }
+
+  public static void main(String[] args) {
+    System.out.println(
+        new ShortestCycleInGraph()
+            .findShortestCycle(
+                7, new int[][] {{0, 1}, {1, 2}, {2, 0}, {3, 4}, {4, 5}, {5, 6}, {6, 3}}));
+
+    System.out.println(
+        new ShortestCycleInGraph()
+            .findShortestCycle(
+                9,
+                new int[][] {
+                  {0, 1}, {1, 2}, {2, 3}, {0, 3}, {3, 4}, {4, 5}, {5, 6}, {7, 8}, {8, 0}
+                }));
+
+    System.out.println(
+        new ShortestCycleInGraph().findShortestCycle(3, new int[][] {{0, 1}, {1, 2}}));
+
+    System.out.println(
+        new ShortestCycleInGraph()
+            .findShortestCycle(
+                6, new int[][] {{4, 1}, {5, 1}, {3, 2}, {5, 0}, {4, 0}, {3, 0}, {2, 1}}));
+
+    // Exception test case;
+    // ans: 4
+    System.out.println(
+        new ShortestCycleInGraph()
+            .findShortestCycle(
+                6, new int[][] {{4, 2}, {5, 1}, {5, 0}, {0, 3}, {5, 2}, {1, 4}, {1, 3}, {3, 4}}));
+  }
+}

From cbddf63e26478fc135d5f5f5294b00ddfdd7b699 Mon Sep 17 00:00:00 2001
From: Subham1999 <subhamsantra2016@gmail.com>
Date: Sat, 31 Aug 2024 00:28:10 +0530
Subject: [PATCH 3/5] LLD

---
 .idea/workspace.xml                           |  19 ++-
 .../graph/CollectCoinsInATree.java            |  20 ++++
 .../com/thealgorithm/lld/ParkingLotLLD.java   | 111 ++++++++++++++++++
 3 files changed, 146 insertions(+), 4 deletions(-)
 create mode 100644 src/main/java/com/thealgorithm/graph/CollectCoinsInATree.java
 create mode 100644 src/main/java/com/thealgorithm/lld/ParkingLotLLD.java

diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index b6f09c1..990891c 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,8 +4,9 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="d1dce324-e0e9-40ed-8855-0f1c77b6fb86" name="Changes" comment="GRAPH">
-      <change afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/ShortestCycleInGraph.java" afterDir="false" />
+    <list default="true" id="d1dce324-e0e9-40ed-8855-0f1c77b6fb86" name="Changes" comment="LC GRAPH HARD ShortestCycleInGraph">
+      <change afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/CollectCoinsInATree.java" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/lld/ParkingLotLLD.java" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
@@ -86,6 +87,7 @@
 }]]></component>
   <component name="RecentsManager">
     <key name="CreateClassDialog.RecentsKey">
+      <recent name="com.thealgorithm.lld" />
       <recent name="com.subham.ta.graph" />
     </key>
   </component>
@@ -398,7 +400,15 @@
       <option name="project" value="LOCAL" />
       <updated>1724954143566</updated>
     </task>
-    <option name="localTasksCounter" value="29" />
+    <task id="LOCAL-00029" summary="LC GRAPH HARD ShortestCycleInGraph">
+      <option name="closed" value="true" />
+      <created>1725033464461</created>
+      <option name="number" value="00029" />
+      <option name="presentableId" value="LOCAL-00029" />
+      <option name="project" value="LOCAL" />
+      <updated>1725033464461</updated>
+    </task>
+    <option name="localTasksCounter" value="30" />
     <servers />
   </component>
   <component name="Vcs.Log.Tabs.Properties">
@@ -429,7 +439,8 @@
     <MESSAGE value="WordSearch.java added" />
     <MESSAGE value="modified the doc" />
     <MESSAGE value="GRAPH" />
-    <option name="LAST_COMMIT_MESSAGE" value="GRAPH" />
+    <MESSAGE value="LC GRAPH HARD ShortestCycleInGraph" />
+    <option name="LAST_COMMIT_MESSAGE" value="LC GRAPH HARD ShortestCycleInGraph" />
   </component>
   <component name="XDebuggerManager">
     <breakpoint-manager>
diff --git a/src/main/java/com/thealgorithm/graph/CollectCoinsInATree.java b/src/main/java/com/thealgorithm/graph/CollectCoinsInATree.java
new file mode 100644
index 0000000..7eafe6d
--- /dev/null
+++ b/src/main/java/com/thealgorithm/graph/CollectCoinsInATree.java
@@ -0,0 +1,20 @@
+package com.thealgorithm.graph;
+
+/**
+ * @author: Subham Santra
+ */
+public class CollectCoinsInATree {
+
+  public int collectTheCoins(int[] coins, int[][] edges) {
+    return 0;
+  }
+
+  public static void main(String[] args) {
+
+    System.out.println(
+        new CollectCoinsInATree()
+            .collectTheCoins(
+                new int[] {1, 0, 0, 0, 0, 1},
+                new int[][] {{0, 1}, {1, 2}, {2, 3}, {3, 4}, {4, 5}}));
+  }
+}
diff --git a/src/main/java/com/thealgorithm/lld/ParkingLotLLD.java b/src/main/java/com/thealgorithm/lld/ParkingLotLLD.java
new file mode 100644
index 0000000..4150004
--- /dev/null
+++ b/src/main/java/com/thealgorithm/lld/ParkingLotLLD.java
@@ -0,0 +1,111 @@
+package com.thealgorithm.lld;
+
+import java.sql.Timestamp;
+import java.time.Instant;
+import java.util.List;
+import lombok.Data;
+
+/**
+ * @author: Subham Santra
+ */
+@Data
+abstract class Vehicle {
+  String vehicleNumber;
+  String registration;
+  String owner;
+}
+
+class Bike extends Vehicle {}
+
+class Car extends Vehicle {}
+
+class Truck extends Vehicle {}
+
+@Data
+abstract class ParkingSpot {
+  int level;
+  int id;
+  boolean isOccupied;
+  Vehicle occupiedVehicle;
+  Timestamp occupiedAt;
+
+  abstract boolean canOccupy(Vehicle vehicle);
+
+  public boolean occupy(Vehicle vehicle) {
+    if (canOccupy(vehicle)) {
+      isOccupied = true;
+      occupiedVehicle = vehicle;
+      occupiedAt = Timestamp.from(Instant.now());
+      return true;
+    }
+    return false;
+  }
+}
+
+class BikeParkingSpot extends ParkingSpot {
+  @Override
+  boolean canOccupy(Vehicle vehicle) {
+    return (vehicle instanceof Bike) && !isOccupied();
+  }
+}
+
+class CarParkingSpot extends ParkingSpot {
+  @Override
+  boolean canOccupy(Vehicle vehicle) {
+    return (vehicle instanceof Car) && !isOccupied();
+  }
+}
+
+class TruckParkingSpot extends ParkingSpot {
+  @Override
+  boolean canOccupy(Vehicle vehicle) {
+    return (vehicle instanceof Car) && !isOccupied();
+  }
+}
+
+class ParkingSpotNotEmptyException extends Exception {
+  public ParkingSpotNotEmptyException(int parkingSpotId) {
+    super(Integer.toString(parkingSpotId));
+  }
+}
+
+@Data
+class Level {
+  int level;
+  List<ParkingSpot> parkingSpots;
+
+  void addMore(ParkingSpot parkingSpot) {
+    parkingSpot.setLevel(level);
+    this.parkingSpots.add(parkingSpot);
+  }
+
+  void remove(int parkingSpotId) throws ParkingSpotNotEmptyException {
+    for (ParkingSpot parkingSpot : parkingSpots) {
+      if (parkingSpot.getId() == parkingSpotId) {
+        if (parkingSpot.isOccupied()) {
+          throw new ParkingSpotNotEmptyException(parkingSpotId);
+        } else {
+          parkingSpots.remove(parkingSpot);
+        }
+      }
+    }
+  }
+
+  ParkingSpot parkThis(Vehicle vehicle) {
+    for (ParkingSpot parkingSpot : parkingSpots) {
+      if (parkingSpot.occupy(vehicle)) {
+        return parkingSpot;
+      }
+    }
+    return null;
+  }
+}
+
+@Data
+class ParkingLot {
+  List<Level> parkingLevels;
+
+  void park(Vehicle vehicle) {}
+}
+
+public class ParkingLotLLD {}

From 5fdd5ca50812c696b2965624df550d5c79172353 Mon Sep 17 00:00:00 2001
From: Subham1999 <subhamsantra2016@gmail.com>
Date: Sat, 31 Aug 2024 12:42:36 +0530
Subject: [PATCH 4/5] PRIMS MST added

---
 .idea/workspace.xml                           |  64 ++++----
 .../java/com/thealgorithm/graph/Edge.java     |   9 ++
 .../java/com/thealgorithm/graph/Graph.java    |   6 +
 .../java/com/thealgorithm/graph/PrimsMST.java | 137 ------------------
 .../graph/PrimsMinimumSpanningTree.java       |  44 ++++++
 .../com/thealgorithm/lld/ParkingLotLLD.java   |   4 +-
 6 files changed, 100 insertions(+), 164 deletions(-)
 delete mode 100644 src/main/java/com/thealgorithm/graph/PrimsMST.java
 create mode 100644 src/main/java/com/thealgorithm/graph/PrimsMinimumSpanningTree.java

diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 990891c..573faac 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,10 +4,13 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="d1dce324-e0e9-40ed-8855-0f1c77b6fb86" name="Changes" comment="LC GRAPH HARD ShortestCycleInGraph">
-      <change afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/CollectCoinsInATree.java" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/lld/ParkingLotLLD.java" afterDir="false" />
+    <list default="true" id="d1dce324-e0e9-40ed-8855-0f1c77b6fb86" name="Changes" comment="LLD">
+      <change afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/PrimsMinimumSpanningTree.java" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/Edge.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/Edge.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/Graph.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/Graph.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/PrimsMST.java" beforeDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/main/java/com/thealgorithm/lld/ParkingLotLLD.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/lld/ParkingLotLLD.java" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -74,30 +77,30 @@
     <option name="hideEmptyMiddlePackages" value="true" />
     <option name="showLibraryContents" value="true" />
   </component>
-  <component name="PropertiesComponent"><![CDATA[{
-  "keyToString": {
-    "ASKED_SHARE_PROJECT_CONFIGURATION_FILES": "true",
-    "RunOnceActivity.OpenProjectViewOnStart": "true",
-    "RunOnceActivity.ShowReadmeOnStart": "true",
-    "SHARE_PROJECT_CONFIGURATION_FILES": "true",
-    "git-widget-placeholder": "back__tracking",
-    "onboarding.tips.debug.path": "/Users/subhamsantra/Projects/Interview/TheAlgorithm/src/main/java/com/subham/ta/Main.java",
-    "settings.editor.selected.configurable": "preferences.lookFeel"
+  <component name="PropertiesComponent">{
+  &quot;keyToString&quot;: {
+    &quot;ASKED_SHARE_PROJECT_CONFIGURATION_FILES&quot;: &quot;true&quot;,
+    &quot;RunOnceActivity.OpenProjectViewOnStart&quot;: &quot;true&quot;,
+    &quot;RunOnceActivity.ShowReadmeOnStart&quot;: &quot;true&quot;,
+    &quot;SHARE_PROJECT_CONFIGURATION_FILES&quot;: &quot;true&quot;,
+    &quot;git-widget-placeholder&quot;: &quot;back__tracking&quot;,
+    &quot;onboarding.tips.debug.path&quot;: &quot;/Users/subhamsantra/Projects/Interview/TheAlgorithm/src/main/java/com/subham/ta/Main.java&quot;,
+    &quot;settings.editor.selected.configurable&quot;: &quot;preferences.lookFeel&quot;
   }
-}]]></component>
+}</component>
   <component name="RecentsManager">
     <key name="CreateClassDialog.RecentsKey">
       <recent name="com.thealgorithm.lld" />
       <recent name="com.subham.ta.graph" />
     </key>
   </component>
-  <component name="RunManager" selected="Application.ShortestCycleInGraph">
-    <configuration name="CombinationSumII" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
-      <option name="MAIN_CLASS_NAME" value="com.thealgorithm.backtracking.CombinationSumII" />
+  <component name="RunManager" selected="Application.PrimsMinimumSpanningTree">
+    <configuration name="MostStonesRemovedSameRowCol" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
+      <option name="MAIN_CLASS_NAME" value="com.thealgorithm.graph.MostStonesRemovedSameRowCol" />
       <module name="TheAlgorithm" />
       <extension name="coverage">
         <pattern>
-          <option name="PATTERN" value="com.thealgorithm.backtracking.*" />
+          <option name="PATTERN" value="com.thealgorithm.graph.*" />
           <option name="ENABLED" value="true" />
         </pattern>
       </extension>
@@ -105,12 +108,12 @@
         <option name="Make" enabled="true" />
       </method>
     </configuration>
-    <configuration name="MostStonesRemovedSameRowCol" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
-      <option name="MAIN_CLASS_NAME" value="com.thealgorithm.graph.MostStonesRemovedSameRowCol" />
+    <configuration name="PalindromePartitioning" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
+      <option name="MAIN_CLASS_NAME" value="com.thealgorithm.backtracking.PalindromePartitioning" />
       <module name="TheAlgorithm" />
       <extension name="coverage">
         <pattern>
-          <option name="PATTERN" value="com.thealgorithm.graph.*" />
+          <option name="PATTERN" value="com.thealgorithm.backtracking.*" />
           <option name="ENABLED" value="true" />
         </pattern>
       </extension>
@@ -118,12 +121,12 @@
         <option name="Make" enabled="true" />
       </method>
     </configuration>
-    <configuration name="PalindromePartitioning" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
-      <option name="MAIN_CLASS_NAME" value="com.thealgorithm.backtracking.PalindromePartitioning" />
+    <configuration name="PrimsMinimumSpanningTree" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
+      <option name="MAIN_CLASS_NAME" value="com.thealgorithm.graph.PrimsMinimumSpanningTree" />
       <module name="TheAlgorithm" />
       <extension name="coverage">
         <pattern>
-          <option name="PATTERN" value="com.thealgorithm.backtracking.*" />
+          <option name="PATTERN" value="com.thealgorithm.graph.*" />
           <option name="ENABLED" value="true" />
         </pattern>
       </extension>
@@ -159,11 +162,11 @@
     </configuration>
     <recent_temporary>
       <list>
+        <item itemvalue="Application.PrimsMinimumSpanningTree" />
         <item itemvalue="Application.ShortestCycleInGraph" />
         <item itemvalue="Application.MostStonesRemovedSameRowCol" />
         <item itemvalue="Application.PalindromePartitioning" />
         <item itemvalue="Application.WordSearch" />
-        <item itemvalue="Application.CombinationSumII" />
       </list>
     </recent_temporary>
   </component>
@@ -408,7 +411,15 @@
       <option name="project" value="LOCAL" />
       <updated>1725033464461</updated>
     </task>
-    <option name="localTasksCounter" value="30" />
+    <task id="LOCAL-00030" summary="LLD">
+      <option name="closed" value="true" />
+      <created>1725044292132</created>
+      <option name="number" value="00030" />
+      <option name="presentableId" value="LOCAL-00030" />
+      <option name="project" value="LOCAL" />
+      <updated>1725044292132</updated>
+    </task>
+    <option name="localTasksCounter" value="31" />
     <servers />
   </component>
   <component name="Vcs.Log.Tabs.Properties">
@@ -440,7 +451,8 @@
     <MESSAGE value="modified the doc" />
     <MESSAGE value="GRAPH" />
     <MESSAGE value="LC GRAPH HARD ShortestCycleInGraph" />
-    <option name="LAST_COMMIT_MESSAGE" value="LC GRAPH HARD ShortestCycleInGraph" />
+    <MESSAGE value="LLD" />
+    <option name="LAST_COMMIT_MESSAGE" value="LLD" />
   </component>
   <component name="XDebuggerManager">
     <breakpoint-manager>
diff --git a/src/main/java/com/thealgorithm/graph/Edge.java b/src/main/java/com/thealgorithm/graph/Edge.java
index 0bdd265..d0bf120 100644
--- a/src/main/java/com/thealgorithm/graph/Edge.java
+++ b/src/main/java/com/thealgorithm/graph/Edge.java
@@ -16,6 +16,10 @@ public static <V> Edge<V, V> createSimpleEdgeUnWeighted(V v1, V v2) {
     return new Edge<>(Vertex.create(v1), Vertex.create(v2), 0D);
   }
 
+  public static <V> Edge<V, V> createEdge(V v1, V v2, double weight) {
+    return new Edge<>(Vertex.create(v1), Vertex.create(v2), weight);
+  }
+
   @Override
   public boolean equals(Object o) {
     if (this == o) return true;
@@ -29,4 +33,9 @@ public boolean equals(Object o) {
   public int hashCode() {
     return Objects.hash(getVertex1(), getVertex2(), getWeight());
   }
+
+  @Override
+  public String toString() {
+    return "<" + vertex1.getKey() + "--" + vertex2.getKey() + "|" + weight + '>';
+  }
 }
diff --git a/src/main/java/com/thealgorithm/graph/Graph.java b/src/main/java/com/thealgorithm/graph/Graph.java
index 51f39ed..abad3c4 100644
--- a/src/main/java/com/thealgorithm/graph/Graph.java
+++ b/src/main/java/com/thealgorithm/graph/Graph.java
@@ -32,4 +32,10 @@ public void addEdge(Edge<K, V> edge) {
       }
     }
   }
+
+  void clear() {
+    vertexSet.clear();
+    edgeSet.clear();
+    isDirected = false;
+  }
 }
diff --git a/src/main/java/com/thealgorithm/graph/PrimsMST.java b/src/main/java/com/thealgorithm/graph/PrimsMST.java
deleted file mode 100644
index 7f79a77..0000000
--- a/src/main/java/com/thealgorithm/graph/PrimsMST.java
+++ /dev/null
@@ -1,137 +0,0 @@
-// package com.subham.ta.graph;
-//
-// import static java.util.Collections.swap;
-//
-// import java.util.ArrayList;
-// import java.util.HashMap;
-// import java.util.List;
-// import java.util.Map;
-// import java.util.Set;
-//
-// public class PrimsMST {
-//  private static final int INF = Integer.MAX_VALUE;
-//
-//  static class Graph {
-//    Map<Integer, Map<Integer, Integer>> edges;
-//    Set<Integer> nodes;
-//
-//    public Graph() {
-//      this.edges = new HashMap<>();
-//    }
-//
-//    void addEdge(int u, int v, int w) {
-//      edges.putIfAbsent(u, new HashMap<>());
-//      edges.get(u).putIfAbsent(v, w);
-//      nodes.add(u);
-//      nodes.add(v);
-//    }
-//
-//    int noOfNodes() {
-//      return nodes.size();
-//    }
-//
-//    Set<Integer> getAllNodes() {
-//      return nodes;
-//    }
-//  }
-//
-//  static class BinaryMinHeap {
-//    int size;
-//    List<Integer> tree;
-//    Map<Integer, Integer> valToIndex;
-//    Map<Integer, Integer> valToWeight;
-//
-//    BinaryMinHeap(int size) {
-//      this.size = size;
-//      this.tree = new ArrayList<>();
-//      this.valToIndex = new HashMap<>();
-//      this.valToWeight = new HashMap<>();
-//    }
-//
-//    public BinaryMinHeap(Graph graph) {
-//      this(graph.noOfNodes());
-//      for (int node : graph.getAllNodes()) {
-//        this.addEntry(node, INF);
-//        heapify(valToIndex.get(node));
-//      }
-//    }
-//
-//    private void heapify(int index) {
-//      if (index <= 0 || index >= this.tree.size()) {
-//        return;
-//      }
-//      int parent = (index - 1) / 2;
-//      if (valToWeight.get(tree.get(parent)) > valToWeight.get(tree.get(index))) {
-//        swap(tree, index, parent);
-//      }
-//      heapify(parent);
-//    }
-//
-//    private void addEntry(int node, int val) {
-//      this.tree.add(node);
-//      this.valToWeight.put(node, val);
-//      this.valToIndex.put(node, this.tree.size() - 1);
-//    }
-//
-//    public void decrease(int node, int newVal) {
-//      int index = valToIndex.get(node);
-//      valToWeight.put(node, newVal);
-//      heapify(index);
-//    }
-//
-//    public int[] getNode(int index) {
-//      return new int[] {tree.get(index), valToWeight.get(tree.get(index))};
-//    }
-//
-//    public int[] extractMin() {
-//      int[] topNode = getNode(0);
-//      int[] lastNode = getNode(tree.size() - 1);
-//
-//      // re-balance the heap
-//
-//      int currentIndex = 0;
-//
-//      swap(tree, tree.size() - 1, 0);
-//      valToIndex.put(lastNode[0], 0);
-//
-//      tree.removeLast();
-//      valToIndex.remove(topNode[0]);
-//      valToWeight.remove(topNode[0]);
-//
-//      while (true) {
-//        int leftChildIndex = (currentIndex * 2) + 1;
-//        int rightChildIndex = (currentIndex * 2) + 2;
-//
-//        int[] leftNode = getNode(leftChildIndex);
-//        int[] rightNode = getNode(rightChildIndex);
-//
-//        if (leftNode[1] < rightNode[1]) {
-//          valToIndex.put(leftNode[0], leftChildIndex);
-//          valToIndex.put()
-//          swap(tree, currentIndex, leftChildIndex);
-//        }
-//      }
-//
-//      return topNode;
-//    }
-//  }
-//
-//  public static void main(String[] args) {
-//    Graph graph = new Graph();
-//
-//    graph.addEdge(1, 2, 1);
-//    graph.addEdge(1, 3, 3);
-//    graph.addEdge(1, 4, 1);
-//    graph.addEdge(3, 4, 2);
-//    graph.addEdge(4, 5, 10);
-//    graph.addEdge(2, 5, 2);
-//
-//    System.out.println(findMST(graph));
-//  }
-//
-//  private static List<int[]> findMST(Graph graph) {
-//    // build binary-min-heap from graph
-//
-//    return null;
-//  }
-// }
diff --git a/src/main/java/com/thealgorithm/graph/PrimsMinimumSpanningTree.java b/src/main/java/com/thealgorithm/graph/PrimsMinimumSpanningTree.java
new file mode 100644
index 0000000..8673948
--- /dev/null
+++ b/src/main/java/com/thealgorithm/graph/PrimsMinimumSpanningTree.java
@@ -0,0 +1,44 @@
+package com.thealgorithm.graph;
+
+import java.util.Comparator;
+import java.util.HashSet;
+import java.util.PriorityQueue;
+import java.util.Set;
+
+/**
+ * @author: Subham Santra
+ */
+public class PrimsMinimumSpanningTree {
+
+  public <K, V> Set<Edge<K, V>> findMST(final Graph<K, V> graph) {
+    Set<Vertex<K, V>> visited = new HashSet<>();
+    PriorityQueue<Edge<K, V>> edgePQ =
+        new PriorityQueue<>(Comparator.comparingDouble(Edge::getWeight));
+    Set<Edge<K, V>> minimumSpanningTree = new HashSet<>();
+
+    edgePQ.addAll(graph.getEdgeSet());
+
+    while ((!edgePQ.isEmpty()) && (visited.size() < graph.getVertexSet().size())) {
+      Edge<K, V> currentMinimumEdge = edgePQ.poll();
+      visited.add(currentMinimumEdge.getVertex1());
+      visited.add(currentMinimumEdge.getVertex2());
+      minimumSpanningTree.add(currentMinimumEdge);
+    }
+
+    return minimumSpanningTree;
+  }
+
+  // Test code
+  public static void main(String[] args) {
+    Graph<Integer, Integer> graph = new Graph<>(false);
+
+    graph.addEdge(Edge.createEdge(1, 2, 4));
+    graph.addEdge(Edge.createEdge(1, 3, 1));
+    graph.addEdge(Edge.createEdge(1, 5, 3));
+    graph.addEdge(Edge.createEdge(5, 4, 1));
+    graph.addEdge(Edge.createEdge(5, 3, 1));
+    graph.addEdge(Edge.createEdge(2, 4, 2));
+
+    System.out.println(new PrimsMinimumSpanningTree().findMST(graph));
+  }
+}
diff --git a/src/main/java/com/thealgorithm/lld/ParkingLotLLD.java b/src/main/java/com/thealgorithm/lld/ParkingLotLLD.java
index 4150004..28204cd 100644
--- a/src/main/java/com/thealgorithm/lld/ParkingLotLLD.java
+++ b/src/main/java/com/thealgorithm/lld/ParkingLotLLD.java
@@ -105,7 +105,9 @@ ParkingSpot parkThis(Vehicle vehicle) {
 class ParkingLot {
   List<Level> parkingLevels;
 
-  void park(Vehicle vehicle) {}
+  void park(final Vehicle vehicle) {
+
+  }
 }
 
 public class ParkingLotLLD {}

From 728ab1e7823bde58d710bf73f590ea98f1f98da1 Mon Sep 17 00:00:00 2001
From: Subham1999 <subhamsantra2016@gmail.com>
Date: Sun, 1 Sep 2024 00:11:43 +0530
Subject: [PATCH 5/5] MAANG - top

---
 .idea/workspace.xml                           | 71 ++++++++++---------
 .../LargestSubMatrixWithRearrangements.java   | 66 +++++++++++++++++
 2 files changed, 104 insertions(+), 33 deletions(-)
 create mode 100644 src/main/java/com/thealgorithm/stacks/LargestSubMatrixWithRearrangements.java

diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 573faac..dac362a 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,13 +4,9 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="d1dce324-e0e9-40ed-8855-0f1c77b6fb86" name="Changes" comment="LLD">
-      <change afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/PrimsMinimumSpanningTree.java" afterDir="false" />
+    <list default="true" id="d1dce324-e0e9-40ed-8855-0f1c77b6fb86" name="Changes" comment="PRIMS MST added">
+      <change afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/stacks/LargestSubMatrixWithRearrangements.java" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/Edge.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/Edge.java" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/Graph.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/Graph.java" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/src/main/java/com/thealgorithm/graph/PrimsMST.java" beforeDir="false" />
-      <change beforePath="$PROJECT_DIR$/src/main/java/com/thealgorithm/lld/ParkingLotLLD.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/com/thealgorithm/lld/ParkingLotLLD.java" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -77,24 +73,37 @@
     <option name="hideEmptyMiddlePackages" value="true" />
     <option name="showLibraryContents" value="true" />
   </component>
-  <component name="PropertiesComponent">{
-  &quot;keyToString&quot;: {
-    &quot;ASKED_SHARE_PROJECT_CONFIGURATION_FILES&quot;: &quot;true&quot;,
-    &quot;RunOnceActivity.OpenProjectViewOnStart&quot;: &quot;true&quot;,
-    &quot;RunOnceActivity.ShowReadmeOnStart&quot;: &quot;true&quot;,
-    &quot;SHARE_PROJECT_CONFIGURATION_FILES&quot;: &quot;true&quot;,
-    &quot;git-widget-placeholder&quot;: &quot;back__tracking&quot;,
-    &quot;onboarding.tips.debug.path&quot;: &quot;/Users/subhamsantra/Projects/Interview/TheAlgorithm/src/main/java/com/subham/ta/Main.java&quot;,
-    &quot;settings.editor.selected.configurable&quot;: &quot;preferences.lookFeel&quot;
+  <component name="PropertiesComponent"><![CDATA[{
+  "keyToString": {
+    "ASKED_SHARE_PROJECT_CONFIGURATION_FILES": "true",
+    "RunOnceActivity.OpenProjectViewOnStart": "true",
+    "RunOnceActivity.ShowReadmeOnStart": "true",
+    "SHARE_PROJECT_CONFIGURATION_FILES": "true",
+    "git-widget-placeholder": "back__tracking",
+    "onboarding.tips.debug.path": "/Users/subhamsantra/Projects/Interview/TheAlgorithm/src/main/java/com/subham/ta/Main.java",
+    "settings.editor.selected.configurable": "editor.preferences.completion"
   }
-}</component>
+}]]></component>
   <component name="RecentsManager">
     <key name="CreateClassDialog.RecentsKey">
       <recent name="com.thealgorithm.lld" />
       <recent name="com.subham.ta.graph" />
     </key>
   </component>
-  <component name="RunManager" selected="Application.PrimsMinimumSpanningTree">
+  <component name="RunManager" selected="Application.LargestSubMatrixWithRearrangements">
+    <configuration name="LargestSubMatrixWithRearrangements" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
+      <option name="MAIN_CLASS_NAME" value="com.thealgorithm.stacks.LargestSubMatrixWithRearrangements" />
+      <module name="TheAlgorithm" />
+      <extension name="coverage">
+        <pattern>
+          <option name="PATTERN" value="com.thealgorithm.stacks.*" />
+          <option name="ENABLED" value="true" />
+        </pattern>
+      </extension>
+      <method v="2">
+        <option name="Make" enabled="true" />
+      </method>
+    </configuration>
     <configuration name="MostStonesRemovedSameRowCol" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
       <option name="MAIN_CLASS_NAME" value="com.thealgorithm.graph.MostStonesRemovedSameRowCol" />
       <module name="TheAlgorithm" />
@@ -147,26 +156,13 @@
         <option name="Make" enabled="true" />
       </method>
     </configuration>
-    <configuration name="WordSearch" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
-      <option name="MAIN_CLASS_NAME" value="com.thealgorithm.backtracking.WordSearch" />
-      <module name="TheAlgorithm" />
-      <extension name="coverage">
-        <pattern>
-          <option name="PATTERN" value="com.thealgorithm.backtracking.*" />
-          <option name="ENABLED" value="true" />
-        </pattern>
-      </extension>
-      <method v="2">
-        <option name="Make" enabled="true" />
-      </method>
-    </configuration>
     <recent_temporary>
       <list>
+        <item itemvalue="Application.LargestSubMatrixWithRearrangements" />
         <item itemvalue="Application.PrimsMinimumSpanningTree" />
         <item itemvalue="Application.ShortestCycleInGraph" />
         <item itemvalue="Application.MostStonesRemovedSameRowCol" />
         <item itemvalue="Application.PalindromePartitioning" />
-        <item itemvalue="Application.WordSearch" />
       </list>
     </recent_temporary>
   </component>
@@ -419,7 +415,15 @@
       <option name="project" value="LOCAL" />
       <updated>1725044292132</updated>
     </task>
-    <option name="localTasksCounter" value="31" />
+    <task id="LOCAL-00031" summary="PRIMS MST added">
+      <option name="closed" value="true" />
+      <created>1725088358813</created>
+      <option name="number" value="00031" />
+      <option name="presentableId" value="LOCAL-00031" />
+      <option name="project" value="LOCAL" />
+      <updated>1725088358813</updated>
+    </task>
+    <option name="localTasksCounter" value="32" />
     <servers />
   </component>
   <component name="Vcs.Log.Tabs.Properties">
@@ -452,7 +456,8 @@
     <MESSAGE value="GRAPH" />
     <MESSAGE value="LC GRAPH HARD ShortestCycleInGraph" />
     <MESSAGE value="LLD" />
-    <option name="LAST_COMMIT_MESSAGE" value="LLD" />
+    <MESSAGE value="PRIMS MST added" />
+    <option name="LAST_COMMIT_MESSAGE" value="PRIMS MST added" />
   </component>
   <component name="XDebuggerManager">
     <breakpoint-manager>
diff --git a/src/main/java/com/thealgorithm/stacks/LargestSubMatrixWithRearrangements.java b/src/main/java/com/thealgorithm/stacks/LargestSubMatrixWithRearrangements.java
new file mode 100644
index 0000000..75c33d0
--- /dev/null
+++ b/src/main/java/com/thealgorithm/stacks/LargestSubMatrixWithRearrangements.java
@@ -0,0 +1,66 @@
+package com.thealgorithm.stacks;
+
+import java.util.Arrays;
+import java.util.Stack;
+
+/**
+ * @author: Subham Santra
+ */
+public class LargestSubMatrixWithRearrangements {
+  public int largestSubmatrix(int[][] matrix) {
+    int m = matrix.length;
+    int n = matrix[0].length;
+    int[][] prefixSum = new int[m][n];
+
+    System.arraycopy(matrix[0], 0, prefixSum[0], 0, n);
+
+    for (int i = 1; i < m; ++i) {
+      for (int j = 0; j < n; ++j) {
+        prefixSum[i][j] = matrix[i][j] == 0 ? 0 : prefixSum[i - 1][j] + matrix[i][j];
+      }
+    }
+
+    int result = 0;
+
+    for (int i = 0; i < m; ++i) { // O(R)
+      // O(ClogC) + O(C) = O(ClogC)
+      Arrays.sort(prefixSum[i]); // O(ClogC)
+      result = Math.max(result, largestHistogram(prefixSum[i])); // O(C)
+    }
+
+    // Overall TC : O(RClogC) -> O(mn(log n))
+    return result;
+  }
+
+  private int largestHistogram(int[] arr) {
+    Stack<int[]> stack = new Stack<>();
+    int[] temp = new int[arr.length];
+    for (int i = 0; i < arr.length; ++i) {
+      int backIndex = i;
+      while (!stack.isEmpty() && (stack.peek()[0] > arr[i])) {
+        backIndex = stack.pop()[1];
+      }
+      temp[i] = arr[i] * (backIndex - i + 1);
+      stack.push(new int[] {arr[i], backIndex, i});
+    }
+    while (!stack.isEmpty()) {
+      temp[stack.peek()[2]] = stack.peek()[0] * (arr.length - stack.peek()[2]);
+      stack.pop();
+    }
+    return Arrays.stream(temp).max().orElse(0);
+  }
+
+  public static void main(String[] args) {
+    System.out.println(
+        new LargestSubMatrixWithRearrangements()
+            .largestSubmatrix(new int[][] {{1, 1, 0}, {1, 0, 1}}));
+
+    System.out.println(
+        new LargestSubMatrixWithRearrangements()
+            .largestSubmatrix(new int[][] {{0, 0, 1}, {1, 1, 1}, {1, 0, 1}}));
+
+    System.out.println(
+        new LargestSubMatrixWithRearrangements()
+            .largestSubmatrix(new int[][] {{1, 0, 1, 1, 0, 1}}));
+  }
+}