# include<iostream> # include<cmath> # include<cstdio> using namespace std; int main(){ //OJ1484 int n,i=0,j,t=1; cin>>n; int a[n][n]; while (t<=n*n){ for (j=i;j<n-i && t<=n*n;j++){ a[i][j]=t++; } for (j=i+1;j<n-i && t<=n*n;j++){ a[j][n-i-1]=t++; } for (j=n-i-2;j>=i && t<=n*n;j--){ a[n-i-1][j]=t++; } for (j=n-i-2;j>i && t<=n*n;j--){ a[j][i]=t++; } i++; } for (i=0;i<n;i++){ for(j=0;j<n;j++){ printf("%4d",a[i][j]); } cout<<endl; } return 0; }