删掉一个元素以后全为 1 的最长子数组

/*
 * Problem: Given a binary array nums, you need to delete one element from it.
 * Return the length of the longest non-empty subarray containing only 1's in the resulting array.
 * If there is no such subarray, return 0.
 * 
 * Approach using Java Streams:
 * 1. Convert the array to a list of lengths of consecutive 1's segments.
 * 2. Calculate the maximum possible length by considering the deletion of one 0.
 */

import java.util.List;
import java.util.ArrayList;
import java.util.stream.Collectors;
import java.util.stream.IntStream;

public class Solution {
    public int longestSubarray(int[] nums) {
        List<Integer> segments = new ArrayList<>();
        int count = 0;
        for (int num : nums) {
            if (num == 1) {
                count++;
            } else {
                segments.add(count);
                count = 0;
            }
        }
        segments.add(count); // Add the last segment

        if (segments.size() == 1) {
            return segments.get(0) == nums.length ? nums.length - 1 : segments.get(0);
        }

        int maxLength = IntStream.range(0, segments.size() - 1)
            .map(i -> segments.get(i) + segments.get(i + 1))
            .max()
            .orElse(0);

        return maxLength + 1;
    }
}