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