#pragma GCC optimize(2)
#pragma GCC optimize(3)
#include <bits/stdc++.h>
using namespace std;
#define endl "\n"
const int N = 100010;

char s[10][N];

int n;
string a,b;

void solve(){
	
	cin >> n;
	cin >> a >> b;
	a = ' ' + a,b = ' ' + b;
	int ca = 0,cb = 0;
	
	for(int i=1;i<=7;i++)
		for(int j=1;j<=n+1;j++)
			s[i][j] = '.';
	
	for(int i=1;i<=n;i++) if(a[i] == '#') ca++;
	for(int i=1;i<=n;i++) if(b[i] == '#') cb++;
	
	if(ca == n and cb == n){
		cout << "Yes" << endl;
		for(int i=1;i<=7;i++){
			for(int j=1;j<=n;j++){
				cout << '#';
			}
			cout << endl;
		}
		return ;
	}		
	
	if(ca == n or cb == n){
		cout << "No" << endl;
		return ;
	}
	
	for(int i=1;i<=n;i++){
		s[1][i] = a[i];
		s[2][i] = a[i] == '#' ? '.' : '#';
		s[6][i] = b[i] == '#' ? '.' : '#';
		s[7][i] = b[i];
	}
	
	int l,r;
	
	for(int i=1;i<=n;i++){
		if(s[2][i] == '.'){
			if(s[2][i-1] == '#' or s[2][i+1] == '#'){
				s[3][i] = '#';
				l = i;
				break;
			}
		}
	}
	
	for(int i=1;i<=n;i++){
		if(s[6][i] == '.'){
			if(s[6][i-1] == '#' or s[6][i+1] == '#'){
				s[5][i] = '#';
				r = i;
				break;
			}
		}
	}
	
	if(l > r) swap(l,r);
	
	if(l + 1 >= r){
		s[4][l] = '#';
	}
	else{
		for(int i=l+1;i<=r-1;i++) s[4][i] = '#';
	}
	
	cout << "Yes" << endl;
	for(int i=1;i<=7;i++){
		for(int j=1;j<=n;j++){
			cout << s[i][j];
		}
		cout << endl;
	}
	return ;
}

int main(){
	ios::sync_with_stdio(0);
	cin.tie(0),cout.tie(0);
	
	int t; cin>>t;
	while(t--){
		solve();
	}
	return 0;
}