change implementation to insertion-sort

sorting.cpp

@@ -4,21 +4,18 @@ using namespace std;
 
 vector<int> sort_custom(vector<int> v)
 {
-    for(int i = 0; i < v.size(); i++)
+    int i, key, j;
+    for (i = 1; i < v.size(); i++)
     {
-        int count = 0;
-        for(int j = 0; j < v.size()-1; j++)
+       key = v[i];
+       j = i-1;
+
+       while (j >= 0 && v[j] > key)
        {
-            if (v[j] > v[j+1]) {
-                count++;
-                int temp = v[j];
-                v[j] = v[j+1];
-                v[j+1] = temp;
-            }
-        }
-        if (count==0) {
-            return v;
+           v[j+1] = v[j];
+           j = j-1;
        }
+       v[j+1] = key;
    }
    return v;
 }