#include<bits/stdc++.h>
using namespace std;
constexpr int N=1000013;
typedef long long ll;
typedef long double ld;
string s[10];
const char v='#'^'.';
void solve(){
    int n;cin>>n;
    cin>>s[1]>>s[7];
    s[2]=s[1];
    int c1=0;
    for(int i=0;i<n;i++)s[2][i]^=v,c1+=s[2][i]=='#';
    s[6]=s[7];
    int c2=0;
    for(int i=0;i<n;i++)s[6][i]^=v,c2+=s[6][i]=='#';
    if(c1==0&&c2==0){
        cout<<"Yes\n";
        for(int i=1;i<=7;i++)cout<<s[1]<<'\n';
        return;
    }
    if(c1==0||c2==0) {
        cout<<"No\n";
        return;
    }
    if(c1<=n/2)s[3]=s[2];else s[3]=s[1];
    if(c2<=n/2)s[5]=s[6];else s[5]=s[7];
    int c3=0;
    s[4]="";
    for(int i=0;i<n;i++)if(s[3][i]=='#'||s[5][i]=='#')s[4]+='.';else s[4]+='#',c3++;
    if(!c3) s[4]=s[3];
    cout<<"Yes\n";
    for(int i=1;i<=7;i++)cout<<s[i]<<'\n';

}
//
signed main(){
    int T=1;cin>>T;
    while(T--) solve();
}