#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define all(x) (x).begin(), (x).end()

int main()
{
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    int T;
    cin >> T;
    while(T--)
    {
        int n;
        cin >> n;
        string s, t;
        cin >> s >> t;
        
        int chk = (s==string(n, '#')) + (t==string(n, '#'));
        if (chk == 1) { cout << "No\n"; continue; }
        cout << "Yes\n";
        
        if(chk == 2)
        {
            for(int i=0; i<7; ++i) cout<<s<<"\n";
            continue;
        }
        
        if(s==string(n, '.') || t==string(n, '.'))
        {
            for(int i=0; i<6; ++i) cout<<s<<"\n";
            cout<<t<<"\n";
            continue;
        }
        
        cout << s << "\n"; string ss="", tt="";
        for(int i=0;i<n;++i) ss+=".#"[s[i]!='#'];
        for(int i=0;i<n;++i) tt+=".#"[t[i]!='#'];
        
        cout << ss << "\n";
        
        int pos1=-1, pos2=-1;
        for(int i=0;i<n;++i)
        {
            if(ss[i]=='.'&&((i>0&&ss[i-1]=='#')||(i+1<n&&ss[i+1]=='#'))) {pos1 = i; break;}
        }
        for(int i=0;i<n;++i)
        {
            if(tt[i]=='.'&&((i>0&&tt[i-1]=='#')||(i+1<n&&tt[i+1]=='#'))) {pos2 = i; break;}
        }
        assert(pos1 != -1 && pos2 != -1);
        
        string sss=string(n, '.'), ttt=string(n, '.'), st = string(n, '.'); sss[pos1] = ttt[pos2] = '#';
        
        cout << sss << "\n";
        
        if(pos1==pos2) st[pos1] = '#';
        else if(abs(pos1-pos2)==1) st[pos1] = '#';
        else 
        {
            for(int i=min(pos1, pos2)+1; i<max(pos1, pos2); ++i) st[i]='#';
        }
        cout << st << "\n";
        
        cout << ttt << "\n";
        
        cout << tt << "\n";
        
        cout << t << "\n";
    }
}