题解 | #空心正方形图案#

int main() { int n = 0; int j = 0; int i = 0; while (scanf("%d", &n)!=-1) { 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; }