description: Monocarp is playing a computer game. Now he wants to complete the first level of this game.
  
  A level is a rectangular grid of 2 rows and n columns. Monocarp controls a character, which starts in cell (1, 1) — at the intersection of the 1-st row and the 1-st column.
  
  Monocarp's character can move from one cell to another in one step if the cells are adjacent by side and/or corner. Formally, it is possible to move from cell (x_1, y_1) to cell (x_2, y_2) in one step if |x_1 - x_2| ≤ 1 and |y_1 - y_2| ≤ 1. Obviously, it is prohibited to go outside the grid.
  
  There are traps in some cells. If Monocarp's character finds himself in such a cell, he dies, and the game ends.
  
  To complete a level, Monocarp's character should reach cell (2, n) — at the intersection of row 2 and column n.
  
  Help Monocarp determine if it is possible to complete the level.
  
  Input
  
  The first line contains a single integer t (1 ≤ t ≤ 100) — the number of test cases. Then the test cases follow. Each test case consists of three lines.
  
  The first line contains a single integer n (3 ≤ n ≤ 100) — the number of columns.
  
  The next two lines describe the level. The i-th of these lines describes the i-th line of the level — the line consists of the characters '0' and '1'. The character '0' corresponds to a safe cell, the character '1' corresponds to a trap cell.
  
  Additional constraint on the input: cells (1, 1) and (2, n) are safe.
  
  Output
  
  For each test case, output YES if it is possible to complete the level, and NO otherwise.
  
  Example
  
  Input
  
  
  4
  3
  000
  000
  4
  0011
  1100
  4
  0111
  1110
  6
  010101
  101010
  
  
  Output
  
  
  YES
  YES
  NO
  YES
  
  Note
  
  Consider the example from the statement.
  
  In the first test case, one of the possible paths is (1, 1) → (2, 2) → (2, 3).
  
  In the second test case, one of the possible paths is (1, 1) → (1, 2) → (2, 3) → (2, 4).
  
  In the fourth test case, one of the possible paths is (1, 1) → (2, 2) → (1, 3) → (2, 4) → (1, 5) → (2, 6).
solution: import java.util.*;
  import java.util.Scanner;
  
  
  public class Solution {
  	static int mod=1000000007;;
  	
  //	 
  	public static void main(String[] args) {
  		// TODO Auto-generated method stub
  		Scanner sc=new Scanner(System.in);
  		int tt=sc.nextInt();
  		
  		
  		while(tt-->0){
  			
  			int n=sc.nextInt();
  			
  			String row1=sc.next();
  			String row2=sc.next();
  			
  			boolean ans=false;
  			Queue<int []> q=new LinkedList<>();
  			boolean vis[][]=new boolean[2][n];
  			
  			for(boolean a[]:vis)Arrays.fill(a, false);
  			
  			
  			
  			q.add(new int[]{0,0});
  			for(int i=0;i<n;i++) {
  				
  				if(row1.charAt(i)=='1') {
  					vis[0][i]=true;
  				}
  				
  			}
  			
  	for(int i=0;i<n;i++) {
  				
  				if(row2.charAt(i)=='1') {
  					vis[1][i]=true;
  				}
  				
  			}
  			
  			vis[0][0]=true;
  			
  			while(!q.isEmpty()) {
  				int temp[]=q.poll();
  				
  				if(temp[0]==1&&temp[1]==n-1) {
  					ans=true;
  					break;
  				}
  				
  				for(int i=-1;i<=1;i++) {
  					
  					for(int j=-1;j<=1;j++) {
  						
  						int x=temp[0]+i;
  						int y=temp[1]+j;
  						
  						if(x<2&&x>=0&&y<n&&y>=0&&!vis[x][y]) {
  							
  							
  							vis[x][y]=true;
  							q.add(new int[]{x,y});
  							
  							
  						}
  						
  						
  					}
  				}
  				
  				
  				
  				
  			}
  			
  			if(ans) {
  				
  				System.out.println("YES");
  			}
  			else {
  				System.out.println("NO");
  			}
  			
  			
  			
  				
  				
  			}	
  		
  			
  		
  			
  		}
  		
  		
  		
  		
  		
  		
  	
  	
  	
  
  }