题解 | #未排序正数数组中累加和为给定值的最长子数组的长度#

import java.util.Scanner;

public class Main {

public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int k = sc.nextInt();
    int[] arr = new int[n];

    for (int i = 0; i < n; i++) {
        arr[i] = sc.nextInt();
    }

    int left = 0;
    int right = 0;
    int sum = arr[left];
    int len = 0;

    while (right < n) {
        if (sum == k) {
            len = Math.max(right - left + 1, len);
            sum -= arr[left++];
        } else if (sum > k) {
            sum -= arr[left++];
        } else {
            right++;
            if (right == n) {
                break;
            }
            sum += arr[right];
        }
    }

    System.out.println(len);
}

}