New to codeing

I am solving this problem Playing with Strings and i am stuck. I don’t know where the code is going wrong , i tried several test case and tried custom input through which getting right output.
here the code is
/* 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
{
// your code goes here
try {

	Scanner sc = new Scanner(System.in);
//	InputStreamReader r=new InputStreamReader(System.in);
//	BufferedReader br = new BufferedReader(r);
	
	int t = sc.nextInt();//Integer.parseInt(br.readLine());
	for(int i=0;i<t;i++)
	{
	    int n =sc.nextInt(); //Integer.parseInt(br.readLine());
	    
	    int S = sc.nextInt();//Integer.parseInt(br.readLine());
	    int R = sc.nextInt();//Integer.parseInt(br.readLine());
	    
	    int first0=0,first1=0,sec0=0,sec1=0;
	    
	    for(int j=0;j<n;j++)
	    {
	        if(S%10==0)
	        {
	            first0++;
	            //System.out.println("first0= "+first0);
	        }
	        else
	        {
	           first1++;
	           //System.out.println("first1= "+first1);
	        }
	        S=S/10;
	        
	        if(R%10==0)
	        {
	            sec0++;
	            //System.out.println("sec0= "+sec0);
	        }
	        else
	        {
	           sec1++;
	           //System.out.println("sec1= "+sec1);
	        }
	        R=R/10;
	    }
	    if(first0==sec0 && first1==sec1)
	    {
	        System.out.println("YES");
	    }
	    else
	    {
	       System.out.println("NO"); 
	    }
	    
	}
	} 
	catch(Exception e) 
	{
	    return;
	}
}

}