#include"bits/stdc++.h"
#define endl '\n'
using ll=long long;
using namespace std;
constexpr int N=1e5+10,inf=0X3F3F3F3F;
constexpr ll INF=0X3F3F3F3F3F3F3F3F;
void solve(){
    int n;
    cin>>n;
    string t,y;
    for(int i=0;i<n;i++){
        t.push_back('#');
        y.push_back('.');
    }
    string a,b;
    cin>>a>>b;
    if((a==t)^(b==t)){
        cout<<"No"<<endl;
        return;
    }else if(a==t and b==t){
        cout<<"Yes"<<endl;
        for(int i=0;i<7;i++)
            cout<<t<<endl;
        return;
    }
    vector<string>mp(7);

    mp[0]=a;
    mp[6]=b;

    mp[1].resize(n);
    for(int i=0;i<n;i++){
        if(a[i]=='.')
            mp[1][i]='#';
        else
            mp[1][i]='.';
    }

    mp[5].resize(n);
    for(int i=0;i<n;i++){
        if(b[i]=='.')
            mp[5][i]='#';
        else
            mp[5][i]='.';
    }

    int u=-1,v=-1;
    for(int i=0;i<n;i++){
        if(mp[1][i]=='.' and ((i>0 and mp[1][i-1]=='#')or(i<n-1 and mp[1][i+1]=='#'))){
            u=i;
            break;
        }
    }
    for(int i=0;i<n;i++){
        if(mp[5][i]=='.' and ((i>0 and mp[5][i-1]=='#')or(i<n-1 and mp[5][i+1]=='#'))){
            v=i;
            break;
        }
    }
    mp[2]=y;
    mp[4]=y;
    mp[2][u]='#';
    mp[4][v]='#';

    mp[3]=y;
    if(u==v){
        mp[3][u]='#';
    }else if(min(u,v)+1==max(u,v)){
        mp[3][u]='#';
    }else{
        for(int i=min(u,v)+1;i<max(u,v);i++)
            mp[3][i]='#';
    }
    
    cout<<"Yes"<<endl;
    for(int i=0;i<7;i++){
        cout<<mp[i]<<endl;
    }
}
signed main(){
    cin.tie(nullptr)->sync_with_stdio(0);
	int t;cin>>t;while(t--)
    solve();
    return 0;
}