题解 | #最长无重复子数组#

import java.util.*;


public class Solution {
    /**
     * 
     * @param arr int整型一维数组 the array
     * @return int整型
     */
    public int maxLength(int[] arr) {
        int len = arr.length;
        if(len <= 1) return 1;
        HashSet set = new HashSet();

        int left = 0, right = 1;
        int maxLen = 1;
        set.add(arr[left]);
        while (right < len && left < right) {
            if (set.contains(arr[right])) {
                while (left < right && set.contains(arr[right])) {
                    set.remove(arr[left]);
                    left++;
                }
            }

            set.add(arr[right]);
            right++;
            int tempMax = right - left;
            maxLen = Math.max(tempMax, maxLen);
        }

        return maxLen;
    }
}