#include<iostream>

#include<iomanip>

using namespace std;

int main()

{

const int N = 21;

int a[N][N] = {0};

int x = 0, y = N / 2;

a[x][y] = 1;

for(int num = 2; num <= N * N; num++)

{

int nx = (x - 1 + N) % N, ny = (y + 1) % N;

if((x == 0 && y == N - 1) || (a[nx][ny] > 0))

{

nx = (x + 1) % N;

ny = y;

}

a[nx][ny] = num;

x = nx;

y = ny;

}

for(int i = 0; i < N; i++)

{

for(int j = 0; j < N; j++)

cout << setw(4) << a[i][j] << " ";

cout << endl;

}

return 0;

}