#include <bits/stdc++.h>
using std::cin;
using std::cout;
using std::string;
typedef long long lli;

int n;
string s1,s2,so;
int i1,i2;
bool m1,m2;
inline bool ck(string &s) {
	for(int i=0;i<s.length();++i)if(s[i]=='.')return 0;
	return 1;
}
inline int ib(int x){return x>0?x:-x;}

inline void solve() {
	cin>>n>>s1>>s2;
	m1=ck(s1),m2=ck(s2);
	if(m1^m2) {
		cout<<"No"<<'\n';
		return;
	}
	cout<<"Yes"<<'\n';
	if(m1&&m2) {
		for(int i=1;i<=7;++i) {
			for(int j=1;j<=n;++j)cout<<'#';
			cout<<'\n';
		}
		return;
	}

	for(int i=1;i<n;++i)if(s1[i-1]=='#'&&s1[i]=='.')i1=i-1;
	for(int i=1;i<n;++i)if(s1[i-1]=='.'&&s1[i]=='#')i1=i;
	for(int i=1;i<n;++i)if(s2[i-1]=='#'&&s2[i]=='.')i2=i-1;
	for(int i=1;i<n;++i)if(s2[i-1]=='.'&&s2[i]=='#')i2=i;
	cout<<s1<<'\n';
	so=s1;
	for(int i=0;i<n;++i)if(so[i]=='.')so[i]='#';else so[i]='.';
	cout<<so<<'\n';
	for(int i=0;i<n;++i)if(i==i1)so[i]='#';else so[i]='.';
	cout<<so<<'\n';
	for(int i=0;i<n;++i) {
		if(ib(i1-i2)>=2) {
			if(i1<i&&i<i2||i2<i&&i<i1)so[i]='#';else so[i]='.';
		}
		else {
			if(i1==i)so[i]='#';else so[i]='.';
		}
	}
	cout<<so<<'\n';
	for(int i=0;i<n;++i)if(i==i2)so[i]='#';else so[i]='.';
	cout<<so<<'\n';
	so=s2;
	for(int i=0;i<n;++i)if(so[i]=='.')so[i]='#';else so[i]='.';
	cout<<so<<'\n';
	cout<<s2<<'\n';
}
inline void clear() {
	i1=i2=0;
}

int main() {
	std::ios::sync_with_stdio(0);
	cin.tie(0),cout.tie(0);

	int t;
	cin>>t;
	while(t--) {
		solve();
		clear();
	}

	return 0;
}