题解 | #空心正方形图案#

#include <stdio.h>

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