题解 | #空心正方形图案#

#include <stdio.h>

int main()
{
    int n ;
    while(scanf("%d", &n) != -1)
    {
        for (int i = 0; i < n ; i++)
        {
            for (int j = 0; j < n; j++)
            {
                if(i == 0|| i == n - 1 || j == 0 || j == n - 1)
                {
                    printf("* ");
                }
                else
                {
                    printf("  ");
                }
            }
            printf("\n");
        }
    }
    return 0;
}