import java.util.*;
 
public class Main {
    // Using 2-pointers
    private static int MaxSubarray(int[] arr, int k){
    	int max = 0;
    	int left = 0, sum = 0;
    	for(int right = 0; right<arr.length; right++){
    		sum+=arr[right];
    		while(sum>k){
    			sum-=arr[left];
    			left++;
    		}
    		if(sum == k) max = Math.max(max,(right - left +1));
    	}
    	return max;
    }
 
    public static void main(String[] args) {
        int[] arr = {1, 2, 3, 4, 5};
        int k = 5;
        System.out.println("Max subarray with sum " + k + ": " + MaxSubarray(arr, k));
    }
}
 

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