typo

Author: WhythZ

_posts/2025-04-22-首次面试后的算法复盘之链表与二叉树.md

@@ -186,7 +186,7 @@ ListNode* getIntersectionNode(ListNode* headA, ListNode* headB)
 }
 ```
 
-- 除了上述巧思解法外，还可引入哈希集合`std::unordered_set`来避免暴力遍历的时间复杂度
+- 除了上述巧思解法外，还可引入哈希集合`unordered_set`来避免暴力遍历的时间复杂度
 
 ```cpp
 // ListNode* getIntersectionNode(ListNode* headA, ListNode* headB)
@@ -1555,7 +1555,7 @@ TreeNode* invertTree(TreeNode* root)
 {
     if (root != nullptr)
     {
-        std::swap(root->left, root->right);
+        swap(root->left, root->right);
         invertTree(root->left);
         invertTree(root->right);
     }

_posts/2025-06-13-数组相关算法的浅浅刷题笔记.md

@@ -162,14 +162,14 @@ void rotate(vector<int>& nums, int k)
 {
     k %= nums.size();
 
-    std::vector<int> _temp;
+    vector<int> _temp;
     _temp.resize(k);
 
     for (int _j = 0; _j < k; _j++)
         _temp[_j] = nums[nums.size() - k + _j];
 
     for (int _i = nums.size() - k - 1; _i >= 0; _i--)
-        std::swap(nums[_i], nums[k + _i]);
+        swap(nums[_i], nums[k + _i]);
     
     for (int _m = 0; _m < k; _m++)
         nums[_m] = _temp[_m];
@@ -244,7 +244,7 @@ vector<int> productExceptSelf(vector<int>& nums)
     for (int left = 0; left < n; left++)
     {
         right = (n - 1) - left;
-        
+
         ans[left] *= lp;
         lp *= nums[left];
 
@@ -255,6 +255,33 @@ vector<int> productExceptSelf(vector<int>& nums)
 }
 ```
 
+- 上面这个有点抽象，下面这个算是兼具效率（不消耗额外空间）和易读性的版本
+
+```cpp
+vector<int> productExceptSelf(vector<int>& nums)
+{
+    int n = nums.size();
+    vector<int> ans; ans.resize(n, 1);
+
+    //从左到右，计算左侧累积乘积
+    int accum = 1;
+    for (int i = 0; i < n; i++)
+    {
+        ans[i] *= accum;
+        accum *= nums[i];
+    }
+    //从右到左，计算右侧累积乘积
+    accum = 1;
+    for (int i = n - 1; i >= 0; i--)
+    {
+        ans[i] *= accum;
+        accum *= nums[i];
+    }
+
+    return ans;
+}
+```
+
 #### [和为K的子数组](https://leetcode.cn/problems/subarray-sum-equals-k/?envType=study-plan-v2&envId=top-100-liked)
 - 暴力枚举法，高时间复杂度，低空间复杂度
 
@@ -657,7 +684,7 @@ vector<int> maxSlidingWindow(vector<int>& nums, int k)
 void bubble(vector<int>& nums, int begin, int end)
 {
     for (int i = begin; i < end; i++)
-        std::swap(nums[i], nums[i+1]);
+        swap(nums[i], nums[i+1]);
 }
 
 void moveZeroes(vector<int>& nums)