#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<queue>
#include<vector>
#define I inline
using namespace std;

const int N = 100100;
char up[N],dn[N];
int ans[8][N];
int n;

I void out() {
	for(int i=1;i<=7;++i) {
		for(int j=1;j<=n;++j) {
			if(ans[i][j]) putchar('#');
			else putchar('.');
		} putchar('\n');
	}
}
I void solve() {
	cin>>n;
	scanf("%s",up+1);
	scanf("%s",dn+1);
	for(int i=1;i<=n+1;++i) 
		for(int j=1;j<=7;++j) ans[j][i]=0;
	for(int i=1;i<=n;++i) {
		ans[1][i]=(up[i]=='#');
		ans[7][i]=(dn[i]=='#');
	}
	bool f1=1,f2=1,c1=1,c2=1;
	for(int i=1;i<=n;++i) {
		if(!ans[1][i]) f1=0;
		if(!ans[7][i]) f2=0; 
		if(ans[1][i]) c1=0;
		if(ans[7][i]) c2=0;
	}
	if(c1&&c2) {
		cout<<"Yes"<<endl;
		out(); return ;
	} else if(c2) {
		cout<<"Yes"<<endl;
		for(int i=1;i<=n;++i) ans[2][i]=1-ans[1][i];
		out();
		return ;
	} else if(c1) {
		cout<<"Yes"<<endl;
		for(int i=1;i<=n;++i) ans[6][i]=1-ans[7][i];
		out();
		return ;
	}
	if(f1&&f2) {
		cout<<"Yes"<<endl;
		for(int i=1;i<=7;++i) {
			for(int j=1;j<=n;++j) putchar('#');
			putchar('\n');
		} 
		return ;
	}
	if(f1||f2) {
		cout<<"No"<<endl;
		return ;
	}
	
	cout<<"Yes"<<endl;
	
	for(int i=1;i<=n;++i) {
		ans[6][i]=1-ans[7][i];
		ans[2][i]=1-ans[1][i];
	}

	int ps1=0,ps2=0;
	for(int i=1;i<=n;++i) {
		if(ans[2][i]==0&&(ans[2][i-1]==1||ans[2][i+1]==1)) {
			ps1=i;
			ans[3][ps1]=1;
			break;
		}
	}
	for(int i=1;i<=n;++i) {
		if(ans[6][i]==0&&(ans[6][i-1]==1||ans[6][i+1]==1)) {
			ps2=i;
			ans[5][ps2]=1;
			break;
		}
	}
	
//	cout<<ps1<<' '<<ps2<<endl;
	if(ps2==ps1||ps2==ps1+1||ps1==ps2+1) {
		ans[4][ps1]=1;
	} else {
		for(int i=max(ps2,ps1)-1;i>=min(ps2,ps1)+1;--i) {
			ans[4][i]=1;
		}
	}
	
	out();
} 
int main()
{
	int T; cin>>T;
	while(T--) {
		solve();
	}
}