/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		// your code goes here
		int[] nums = {1, -1, 5, -2, 3} ;
		int k = 3 ;//, the subarray [1, -1, 5, -2] sums to 3 and has length 4
		int maxlen = 0;
		HashMap<Integer, Integer> mp = new HashMap<>();
		mp.put(0, 1);
		int n = nums.length;
		int sum = 0;
		for(int i=0, j=0; j<n; j++){
			sum += nums[j];
			while(i<=j && sum>k){
				sum-=nums[i];
				i++;
			}
			if(sum ==k){
				maxlen = Math.max(maxlen, j-i+1);
			}
		}
		System.out.println(maxlen);
	}
}