

//Shrey Dubey


#include<iostream>
#include<string>
#include<algorithm>
#include<map>
#include<unordered_map>
#include<vector>
#include<set>
#include<list>
#include<iomanip>
#include<queue>
#include<stack>
#include <math.h>
#include<climits>
#include<bitset>
#include<cstring>
#include<numeric>
#include<array>


using namespace std;
typedef long long ll;
typedef long double ld;

#define YES cout<<"YES\n"
#define Yes cout<<"Yes\n"
#define NO cout<<"NO\n"
#define No cout<<"No\n"
#define prDouble(x) cout<<fixed<<setprecision(10)<<x //to print decimal numbers
#define pb push_back
#define ff first
#define sec second
#define umap unordered_map
#define mp make_pair
#define KOBE ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
#define fo(n) for(ll i = 0; i<n; i++)
#define fnd(stl, data) find(stl.begin(), stl.end(), data)
#define forn(x,n) for(ll x = 0; x<n; x++)
#define imax INT_MAX
#define lmax LLONG_MAX
#define imin INT_MIN
#define lmin LLONG_MIN
#define vi vector<int>
#define vl vector<ll>
#define vp vector<pair<ll,ll> >
#define vb vector<bool>
#define pr(t) cout<<t<<"\n"
#define int long long
#define ql queue<ll>
#define qp queue<pair<ll,ll> >
#define endl "\n"
#define nl cout<<"\n"
#define re cin >>
#define pll pair<ll,ll>
#define FOR(a,b) for(ll i = a; i<=b; i++)
#define all(x) x.begin(),x.end()

ll mod = 1e9 + 7;

ll cl(ld a){
    if(a>(ll) a){
        return (ll)a+1;
    }
    else{
        return (ll)a;
    }
}

ll flr(ld a){
    return (ll) a;
}



//code starts here

const ll M = 310;
ll n; char mat[M][M];

void display(vp &c){
    for(auto p: c){
        mat[p.ff][p.sec] = 'O';
    }
    forn(i,n){
        forn(j,n) cout<<mat[i][j];nl;
    }
}

void solve(){
    re n;
    vp c0,c1,c2;
    forn(i,n) forn(j,n){
        re mat[i][j];
        if((i+j)%3 == 0 && mat[i][j] == 'X') c0.pb(mp(i,j));
        if((i+j)%3 == 1 && mat[i][j] == 'X') c1.pb(mp(i,j));
        if((i+j)%3 == 2 && mat[i][j] == 'X') c2.pb(mp(i,j));
    }
    // cout<<c0.size()<<" "<<c1.size()<<" "<<c2.size()<<"\n";
    if(c0.size()<=c1.size() && c0.size()<=c2.size()){
        display(c0);
        return;
    }
    if(c1.size()<=c0.size() && c1.size()<=c2.size()){
        display(c1);
        return;
    }
    if(c2.size()<=c0.size() && c2.size()<=c1.size()){
        display(c2);
        return;
    }
}

int32_t main(){
    KOBE;
    ll t;
    re t;
    // t = 1;
    while(t--) solve();
}


//common errors
// row - n, col - m always and loop var
// see the freq of numbers carefully
// see if there's array overflow
// use map for large inputs


//problem ideas
//check piegonhole wherever possible
//there might be many instances of limited answers like 0,1,2 only
// see suffix and prefix
//don't be obsessed with binary search
// try to find repeating pattern in matrices
