Help me in solving AMMEAT problem

help
,
1

My issue

getting run time error

My code

/* package codechef; // 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 Codechef
{
	public static void main (String[] args) throws java.lang.Exception
	{
		Scanner sc = new Scanner(System.in);
		
		int t = sc.nextInt();
		
		while(t-- > 0 ){
		    int n = sc.nextInt();
		    int x=sc.nextInt();
		    
		    int a[] = new int[n];
		    
		    for (int i = 0 ; i < n ; i++ ) a[i] = sc.nextInt();
		    
		    Arrays.sort( a );
		    int total=0;
		    boolean flag=false;
		    for(int i=n-1;i>=0;i--) {
		    	total=total+a[i];
		    	if(total>=x){
		    		flag=true;
		    		
		    		System.out.println(n-i);
		    		break;
		    		
		    	}
		    }
		    if(flag!=true)
				System.out.println( -1 );
	}
	}
}

Learning course: Sorting using Java
Problem Link: CodeChef: Practical coding for everyone