题解 | 最长无重复子数组

import java.util.*;


public 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 (int[] arr) {
        if (arr.length == 1){
            return 1;
        }
        Map<Integer, Integer> map = new HashMap<Integer, Integer>();
        int maxLength = 0;
        int left = 0;
        map.put(arr[0], 1);
        int right = 1;
        while (right < arr.length) {
            Integer count = map.getOrDefault(arr[right], 0);
            if (count == 0) {
                int currenLength = right - left + 1;
                if (currenLength > maxLength) {
                    maxLength = currenLength;
                }
                map.put(arr[right], 1);
                right++;
            } else {
                while (arr[left] != arr[right]) {
                    map.put(arr[left], 0);
                    left++;
                }
                map.put(arr[left], 0);
                left++;
            }
        }
        return maxLength;
    }
}