// SudokuSolver

#include <iostream>

#include <cmath>

using namespace std;

bool isSafeToPut(int board[][9],int n,int number,int i,int j){

for(int k =0;k<n;k++){

if(board[k][j] == number || board[i][k]==number){

return false;

}

}

n = sqrt(n);

int starti = (i/n)*n;

int startj = (j/n)*n;

for(int k=starti;k<starti+n;k++){

for(int l=startj;l<startj+n;l++){

if(board[k][l]==number){

return false;

}

}

}

return true;

}

bool SudokuSolver(int board[][9],int n,int i,int j){

// Base Case

if(i==n){

// Print the board

for(int k=0;k<n;k++){

for(int l=0;l<n;l++){

cout<<board[k][l]<<" ";

}

cout<<endl;

}

cout<<endl;

return true;

}

if(j==n){

return SudokuSolver(board,n,i+1,0);

}

if(board[i][j]!=0){

return SudokuSolver(board,n,i,j+1);

}

//Recursive case

for(int number = 1; number <= n ; number++){

if(isSafeToPut(board,n,number,i,j)){

board[i][j] = number; // Place the number

bool KyaBaakiBaatBani = SudokuSolver(board,n,i,j+1);

if(KyaBaakiBaatBani){

return true;

}

board[i][j] = 0;

}

}

return false;

}

int main(){

int n;

cin>>n;

int mat[9][9];

for(int k=0;k<n;k++){

for(int l=0;l<n;l++){

cin>>mat[k][l];

}

}

cout<<"---------------------------"<<endl;

SudokuSolver(mat,n,0,0);

return 0;

}