题解 | #最长无重复子数组#

using System;
using System.Collections.Generic;


class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param arr int整型一维数组 the array
     * @return int整型
     */
    public int maxLength (List<int> arr) {
        int left = 0, right = 0;
        int len = 0;
        int start = 0;
        Dictionary<int, int> dic = new Dictionary<int, int>();
        while(right < arr.Count){
            if(!dic.ContainsKey(arr[right])) dic[arr[right]] = 0;
            dic[arr[right]]++;
            while(dic[arr[right]] > 1){
                dic[arr[left++]]--;
            }
            if(right - left + 1 > len){
                start = left;
                len = right - left + 1;
            }
            right++;
        }
        return len;
    }
}