题解 | #空心正方形图案#

#include <stdio.h>

int main()
{
	int n = 0;
	while (scanf("%d", &n) != EOF)
	{
		int i, j;
		char arr[20][20];
		for (i = 0; i < n; i++)
		{
			for (j = 0; j < n; j++)
			{
				if (i == 0 || i == n - 1 || j == 0 || j == n - 1)
					arr[i][j] = '*';
				else
					arr[i][j] = ' ';
				printf("%c ", arr[i][j]);
			}
			printf("\n");

		}
	}
	return 0;
}