代码随想录算法训练营第六十一天|503.下一个更大元素II、 42. 接雨水

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503.下一个更大元素II

题目链接：503.下一个更大元素II
文章链接
状态：做出来了。

代码

class Solution {
public:
    vector<int> nextGreaterElements(vector<int>& nums) {
        
        vector<int> nums1(nums.begin(), nums.end());
        nums.insert(nums.end(), nums1.begin(), nums1.end());
        
        vector<int> result(nums.size(), -1);
        if (nums.size() == 0) return result;

        
        stack<int> st;
        st.push(0);
        for (int i = 1; i < nums.size(); i++) { 
            if (nums[i] < nums[st.top()]) st.push(i); 
            else if (nums[i] == nums[st.top()]) st.push(i);
            else { 
                while (!st.empty() && nums[i] > nums[st.top()]) {
                    result[st.top()] = nums[i];
                    st.pop();
                }
                st.push(i);
            }
        }
        result.resize(nums.size() / 2);
        return result;
    }
};

42. 接雨水

题目链接：42. 接雨水
文章链接
状态：做出来了

代码

class Solution {
public:
    int trap(vector<int>& height) {
        int sum = 0;
        for (int i = 0; i < height.size(); i++) {
            
            if (i == 0 || i == height.size() - 1) continue;

            int rHeight = height[i];
            int lHeight = height[i]; 
            for (int r = i + 1; r < height.size(); r++) {
                if (height[r] > rHeight) rHeight = height[r];
            }
            for (int l = i - 1; l >= 0; l--) {
                if (height[l] > lHeight) lHeight = height[l];
            }
            int h = min(lHeight, rHeight) - height[i];
            if (h > 0) sum += h;
        }
        return sum;
    }
};