diff --git a/docs/chapter_computational_complexity/time_complexity.md b/docs/chapter_computational_complexity/time_complexity.md
index 09aee7b79..def052c92 100644
--- a/docs/chapter_computational_complexity/time_complexity.md
+++ b/docs/chapter_computational_complexity/time_complexity.md
@@ -1434,11 +1434,14 @@ $$
         for (int i = n - 1; i > 0; i--) {
             // 内循环：冒泡操作
             for (int j = 0; j < i; j++) {
-                // 交换 nums[j] 与 nums[j + 1]
-                int tmp = nums[j];
-                nums[j] = nums[j + 1];
-                nums[j + 1] = tmp;
-                count += 3;  // 元素交换包含 3 个单元操作
+                if (nums[j] > nums [j + 1]) 
+                {
+                    // 交换 nums[j] 与 nums[j + 1]
+                    int tmp = nums[j];
+                    nums[j] = nums[j + 1];
+                    nums[j + 1] = tmp;
+                    count += 3;  // 元素交换包含 3 个单元操作
+                }
             }
             
         }