题解 | 空心正方形图案

#include <stdio.h>

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