feat: update bubble sort algorithm (doocs#827)

Author: yanglbme

basic/sorting/BubbleSort/BubbleSort.cpp

@@ -0,0 +1,31 @@
+#include <iostream>
+#include <vector>
+
+using namespace std;
+
+
+void bubbleSort(vector<int>& arr)
+{
+    int n = arr.size();
+    for (int i = 0; i < n - 1; ++i)
+    {
+        bool change = false;
+        for (int j = 0; j < n - i - 1; ++j)
+        {
+            if (arr[j] > arr[j + 1])
+            {
+                swap(arr[j], arr[j + 1]);
+                change = true;
+            }
+        }
+        if (!change) break;
+    }
+}
+
+int main()
+{
+    vector<int> arr = {9, 8, 7, 6, 5, 4, 3, 2, 1, 0};
+    bubbleSort(arr);
+    for (int v : arr) cout << v << " ";
+    cout << endl;
+}

basic/sorting/BubbleSort/README.md

@@ -101,67 +101,34 @@ func main() {
 ```cpp
 #include <iostream>
 #include <vector>
-#include <string>
 
 using namespace std;
 
-/* 简单版本 */
-void bubblesort(vector<int> &vec)
-{
-    for (int i = 0; i < vec.size() - 1; i++)
-    {
-        for (int j = 0; j < vec.size() - i - 1; j++)
-        {
-            if (vec[j] > vec[j + 1])
-            {
-                swap(vec[j], vec[j + 1]);
-            }
-        }
-    }
-}
 
-/* 改进版本 */
-void bubblesort1(vector<int> &vec)
+void bubbleSort(vector<int>& arr)
 {
-    for (int i = 0; i < vec.size() - 1; i++)
+    int n = arr.size();
+    for (int i = 0; i < n - 1; ++i)
     {
-        bool exchange = false;
-        for (int j = 0; j < vec.size() - i - 1; j++)
+        bool change = false;
+        for (int j = 0; j < n - i - 1; ++j)
         {
-            if (vec[j] > vec[j + 1])
+            if (arr[j] > arr[j + 1])
             {
-                swap(vec[j], vec[j + 1]);
-                exchange = true;
+                swap(arr[j], arr[j + 1]);
+                change = true;
             }
         }
-
-        if (!exchange)
-        {
-            break;
-        }
+        if (!change) break;
     }
 }
 
-void printvec(const vector<int> &vec, const string &strbegin = "", const string &strend = "")
+int main()
 {
-    cout << strbegin << endl;
-    for (auto val : vec)
-    {
-        cout << val << "\t";
-    }
-
+    vector<int> arr = {9, 8, 7, 6, 5, 4, 3, 2, 1, 0};
+    bubbleSort(arr);
+    for (int v : arr) cout << v << " ";
     cout << endl;
-    cout << strend << endl;
-}
-
-int main(void)
-{
-    vector<int> vec = {9, 8, 7, 6, 5, 4, 3, 2, 1, 0};
-    printvec(vec);
-
-    bubblesort1(vec);
-
-    printvec(vec, "after sort", "");
 }
 ```