1335D - Anti-Sudoku - CodeForces Solution

#include <iostream>
#include <bits/stdc++.h>
using namespace std;
#define max(a, b) (a < b ? b : a)
#define min(a, b) ((a > b) ? b : a)
#define mod 1000000007
#define f(a, c) for (int(a) = 0; (a) < (c); (a)++)
#define fl(a, b, c) for (int(a) = (b); (a) <= (c); (a)++)
#define fr(a, b, c) for (int(a) = (b); (a) >= (c); (a)--)
#define all(a) a.begin(), a.end()
#define INF 1000000000000000003
typedef long long int ll;
typedef vector<int> vi;
typedef pair<int, int> pi;
#define pb push_back
#define pob pop_back
#define mp make_pair
long long sqr(long long x)
{
    long long y = sqrt(x) + 5;
    while(y * y > x)
        y--;
    return y;
}
//--------------------------------------------------------------------------
void solve()
{
    vector<string> s(9);
    f(i, 9)
        cin >> s[i];
    f(i, 9)
    {
        f(j, 9)
        {
            if(s[i][j] == '1')
                s[i][j] = '2';
        }
    }
    f(i, 9)
    {
        f(j, 9)
            cout << s[i][j];
        cout << endl;
    }
}
//--------------------------------------------------------------------------
int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    int T = 1;
    cin >> T;
    while (T--) 
    {
        solve();
    }
    return 0;
}