Cleanup bubble sort code for C and C++

- remove random generator function
- use nested loop instead of is_sorted var

Author: mika314

chapters/sorting_searching/bubble/bubble_sort.md

@@ -13,7 +13,9 @@ This means that we need to go through the vector $$\mathcal{O}(n^2)$$ times with
 {% sample lang="cs" %}
 [import:9-27, lang:"csharp"](code/csharp/BubbleSort.cs)
 {% sample lang="c" %}
-[import:4-22, lang:"c_cpp"](code/c/bubble_sort.c)
+[import:11-23, lang:"c_cpp"](code/c/bubble_sort.c)
+{% sample lang="cpp" %}
+[import:13-23, lang:"c_cpp"](code/c++/bubble_sort.cpp)
 {% sample lang="java" %}
 [import:2-12, lang:"java"](code/java/bubble.java)
 {% sample lang="js" %}

chapters/sorting_searching/bubble/code/c++/bubble_sort.cpp

@@ -0,0 +1,35 @@
+#include <algorithm>
+#include <cstddef>
+#include <iostream>
+#include <iterator>
+
+template <class Iter>
+void print_range(Iter first, Iter last) {
+  for (auto it = first; it != last; ++it)
+    std::cout << *it << " ";
+  std::cout << std::endl;
+}
+
+template <class Iter>
+void bubble_sort(Iter first, Iter last) {
+  for (auto it1 = last; it1 != first; --it1) {
+    for (auto it2 = first; it2 + 1 != it1; ++it2) {
+      // these are unsorted! gotta swap 'em
+      if (*(it2 + 1) < *it2) {
+        std::swap(*it2, *(it2 + 1));
+      }
+    }
+  }
+}
+
+int main() {
+  int input[] = {1, 45, 756, 4569, 56, 3, 8, 5, -10, -4};
+
+  std::cout << "Unsorted array:\n";
+  print_range(std::begin(input), std::end(input));
+
+  bubble_sort(std::begin(input), std::end(input));
+
+  std::cout << "\nSorted array:\n";
+  print_range(std::begin(input), std::end(input));
+}

chapters/sorting_searching/bubble/code/c++/bubblesort.cpp

@@ -1,42 +1,38 @@
 #include <stdio.h>
 #include <stddef.h>
 
-void bubble_sort(int *array, size_t n) {
-    int swapped = 0;
-    for (size_t i = 0; i < n - 1; ++i) {
-        swapped = 0;
-        for (size_t j = 0; j < n - i - 1; ++j) {
-            if (array[j] > array[j + 1]) {
-                int tmp = array[j];
-                array[j] = array[j + 1];
-                array[j + 1] = tmp;
+void print_range(int *array, size_t n) {
+    for (size_t i = 0; i < n; ++i) {
+        printf("%d ", array[i]);
+    }
+    printf("\n");
+}
 
-                swapped = 1;
+void bubble_sort(int *array, size_t n) {
+    for (size_t j = n; j > 0; --j) {
+        for (size_t i = 0; i < j - 1; ++i) {
+            for (size_t j = 0; j < n - i - 1; ++j) {
+                if (array[j] > array[j + 1]) {
+                    int tmp = array[j];
+                    array[j] = array[j + 1];
+                    array[j + 1] = tmp;
+                }
             }
         }
-
-        if (!swapped) {
-            break;
-        }
     }
 }
 
 int main() {
-    int array[10] = {1, 45, 756, 4569, 56, 3, 8, 5, -10, -4};
+    const int N = 10;
+    int array[N] = {1, 45, 756, 4569, 56, 3, 8, 5, -10, -4};
 
     printf("Unsorted array:\n");
-    for (size_t i = 0; i < 10; ++i) {
-        printf("%d ", array[i]);
-    }
-    printf("\n\n");
+    print_range(array, N);
 
-    bubble_sort(array, 10);
+    bubble_sort(array, N);
 
-    printf("Sorted array:\n");
-    for (size_t i = 0; i < 10; ++i) {
-        printf("%d ", array[i]);
-    }
-    printf("\n");
+    printf("\nSorted array:\n");
+    print_range(array, N);
 
     return 0;
 }