题解 | #最长无重复子数组#

class Solution {
public:
    /**
     * 
     * @param arr int整型vector the array
     * @return int整型
     */
    int maxLength(vector<int>& arr) {
        // write code here
        int n = arr.size();
        unordered_set<int> dic;
        int l = 0;
        int maxlen = 0;
        for(int i = 0; i < n; i++){
            while(dic.find(arr[i]) != dic.end()){
                dic.erase(arr[l]);
                l++;
            }
            dic.insert(arr[i]);
            maxlen = max(maxlen, i - l + 1);
        }
        return maxlen;
    }
};