# include<iostream> using namespace std; int main(){ int n, way=1, juzhen[21][21]={0}, m=1; cin>>n; for(int i = 0; i < n/2+n%2; i++){ for(int j = i; j < n-i-1; j++){ juzhen[i][j]=m; m++; } for(int j = i; j < n-i-1; j++){ juzhen[j][n-i-1]=m; m++; } for(int j = n-i-1; j > i; j--){ juzhen[n-i-1][j]=m; m++; } for(int j = n-i-1; j > i; j--){ juzhen[j][i]=m; m++; } } for(int i = 0; i < n; i++){ for(int j = 0; j < n; j++)cout<<juzhen[i][j]<<" "; cout<<endl; } return 0; }