给定一个数组找出不含重复数字的最长子数组的长度用java

可以使用滑动窗口的方法来解决这个问题。

import java.util.HashSet;

public class LongestSubarrayWithoutDuplicates {
    public static int findLongestSubarrayLength(int[] nums) {
        int n = nums.length;
        int maxLength = 0;
        int left = 0;
        int right = 0;
        HashSet<Integer> set = new HashSet<>();

        while (right < n) {
            if (!set.contains(nums[right])) {
                set.add(nums[right]);
                maxLength = Math.max(maxLength, right - left + 1);
                right++;
            } else {
                set.remove(nums[left]);
                left++;
            }
        }

        return maxLength;
    }

    public static void main(String[] args) {
        int[] nums = {1, 2, 3, 1, 2, 3, 4, 5};
        int maxLength = findLongestSubarrayLength(nums);
        System.out.println("The length of the longest subarray without duplicates is: " + maxLength);
    }
}

输出结果为：

The length of the longest subarray without duplicates is: 5

时间复杂度：O(n) 空间复杂度：O(k)，其中 k 是数组中不重复数字的个数。