#include <iostream> using namespace std; int n; int t,b,l,r; int num = 1; int a[1001][1001]; int main() { cin>>n; t = 1; l = 1; b = n; r = n; while(num <= n*n){ for(int j = l;j<=r;j++){ a[t][j]=num; num++; } t++; for(int i = t;i <= b;i++){ a[i][r] = num; num++; } r--; for(int j = r;j >= l;j--){ a[b][j] = num; num++; } b--; for(int i = b;i >= t;i--){ a[i][l]=num; num++; } l++; } for(int i = 1; i <= n;i++){ for(int j = 1;j <= n;j++){ printf("%4d",a[i][j]); } printf("\n"); } return 0; }