#include<iostream> #include<cmath> #include<cstdio> #include<cstring> using namespace std; int main() //主函数入口 { int i = 0,j = 0,n = 0,m = 0,num = 1; int arr[20][20] = {0}; scanf("%d",&n); if(n%2 != 0) m = n/2+1; else m = n/2; for(i = 0; i < m; i++) { for(j = i; j < n-i;j++) { arr[i][j] = num++; } for(j = 1+i; j < n-i;j++) { arr[j][n-i-1] = num++; } for(j = n-i-2; j >=i ;j--) { arr[n-i-1][j] = num++; } for(j = n-i-2; j >=i+1 ;j--) { arr[j][i] = num++; } } for(i = 0; i < n; i++) { printf("%4d",arr[i][0]); for(j = 1;j < n;j++) printf("%4d",arr[i][j]); printf("\n"); } return 0; //结束整个程序 }