题解 | #空心正方形图案#

#include <stdio.h>

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