#include<bits/stdc++.h>
#define int long long
#define ll long long
#define endl '\n'
using namespace std;
const int N=1e5+5;
int n;
string a,b;
char c[10][N];
int op[2];
void pri()
{
	cout<<"Yes"<<endl;
	for(int i=1;i<=7;i++)
	{
		for(int j=1;j<=n;j++)
			cout<<c[i][j];
		cout<<endl;
	}
	return;
}
bool check()
{
	vector<pair<int,int> > p[2];
	for(int k=0;k<2;k++)
	{
		for(int i=1;i<=n;i++)
		{
			if(c[op[k]][i]=='.')
			{
				if(!p[k].empty()&&(p[k].back()).second==i-1)
					p[k][p[k].size()-1].second++;
				else
					p[k].push_back({i,i});
			}
		}
	}
//	cout<<"#0"<<endl;
//	for(auto [l,r] : p[0])
//		cout<<l<<" "<<r<<endl;
//	cout<<"#1"<<endl;
//	for(auto [l,r] : p[1])
//		cout<<l<<" "<<r<<endl;
	for(auto[t1,t2]: p[0])
	{
		int s1,s2;
		if(p[1].back().second<t1||p[1].front().first>t2)
			continue;
		int l=0,r=p[1].size()-1;
		while(l<r)
		{
			int mid=(l+r)>>1;
			if(p[1][mid].second>=t1)
				r=mid;
			else
				l=mid+1;
		}
		s1=l;
		l=0,r=p[1].size()-1;
		while(l<r)
		{
			int mid=(l+r+1)>>1;
			if(p[1][mid].first<=t2)
				l=mid;
			else
				r=mid-1;
		}
		s2=l;
		for(int i=s1;i<=s2;i++)
		{
			int l1=max(p[1][i].first,t1),r1=min(p[1][i].second,t2);
			if((l1==p[1][i].first&&r1==t2)||(r1==p[1][i].second&&l1==t1))
			{
				for(int k=l1;k<=r1;k++)
				{
					for(int j=op[0]+1;j<op[1];j++)
						c[j][k]='#';
				}
				pri();
				return true;
			}
		}
	}
	return false;
}
void solve(){
	cin>>n>>a>>b;
	int c1=0,c2=0;
	for(int i=1;i<=7;i++)
		for(int j=1;j<=n;j++)
			c[i][j]='.';
	for(int i=1;i<=n;i++)
		c1+=(a[i-1]=='#'),c2+=(b[i-1]=='#');
	if(c1==n||c2==n){
		if(c1==n&&c2==n){
			cout<<"Yes"<<endl;
			for(int i=1;i<=7;i++){
				for(int j=1;j<=n;j++)
					cout<<'#';
				cout<<endl;
			}
		}else cout<<"No"<<endl;
		return;
	}
	for(int i=1;i<=n;i++)c[1][i]=a[i-1];
	for(int i=1;i<=n;i++)c[7][i]=b[i-1];
	for(int i=1;i<=n;i++){
		c[2][i]=(c[1][i]=='#'?'.':'#');
		c[6][i]=(c[7][i]=='#'?'.':'#');
	}
	op[0]=2,op[1]=6;
	if(check())
		return;
	op[0]++;
	for(int i=1;i<=n;i++)
		c[3][i]=(c[2][i]=='#'?'.':'#');
//	pri();
	bool flag=check();
	assert(flag);
	return ;
}
int T=1;
signed main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	cin>>T;
	for(int kase=1;kase<=T;kase++){
		solve();
	}
	return 0;
}
/*
4
4
#..#
.##.
5
##.#.
.#.##
6
######
.####.
27
.######.######.####.#.#####
.####...####..#.......#####
*/