Create Diameter_of_tree.cpp

Author: RohanVolety

Trees/Diameter_of_tree.cpp

@@ -0,0 +1,60 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+/* Tree node structure used in the program */
+struct Node
+{
+    int data;
+    Node *left, *right;
+};
+
+/* Function to find height of a tree */
+int height(Node *root, int &ans)
+{
+    if (root == NULL)
+        return 0;
+
+    int left_height = height(root->left, ans);
+
+    int right_height = height(root->right, ans);
+
+    // update the answer, because diameter of a
+    // tree is nothing but maximum value of
+    // (left_height + right_height + 1) for each node
+    ans = max(ans, 1 + left_height + right_height);
+
+    return 1 + max(left_height, right_height);
+}
+
+/* Computes the diameter of binary tree with given root. */
+int diameter(Node *root)
+{
+    if (root == NULL)
+        return 0;
+    int ans = INT_MIN; // This will store the final answer
+    height(root, ans);
+    return ans;
+}
+
+struct Node *newNode(int data)
+{
+    struct Node *node = new Node;
+    node->data = data;
+    node->left = node->right = NULL;
+
+    return (node);
+}
+
+// Driver code
+int main()
+{
+    struct Node *root = newNode(1);
+    root->left = newNode(2);
+    root->right = newNode(3);
+    root->left->left = newNode(4);
+    root->left->right = newNode(5);
+
+    printf("Diameter is %d\n", diameter(root));
+
+    return 0;
+}