滑动窗口C++

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209. 长度最小的子数组

class Solution {
public:
    int minSubArrayLen(int target, vector<int> nums) {
        int left,right=0;
        int curSum=0;
        int minLen=0;
        while(right<nums.size()){
            curSum+=nums.at(right);
            while(curSum>=target){
                if(right-left+1<minLen || minLen==0){
                    minLen=right-left+1;
                }
                curSum-=nums.at(left);
                left++;
            }
            right++;
        }
        return minLen;
    }
};

3. 无重复字符的最长子串

class Solution {
public:
    int lengthOfLongestSubstring(string s) {
        int left,right=0;
        int maxLen=0;
        unordered_map<char,int> umap;
        while(right<s.length()){
            umap[s[right]]++;
            while(umap[s[right]]!=1){
                umap[s[left]]--;
                left++;
            }
            maxLen=max(maxLen,right-left+1);
            right++;
        }
        return maxLen;

    }
};