8.输出空心菱形

include <stdio.h>

void main() {
/n：代表菱形边长/
int i, j, n = 5;
/打印上三角/
for (i = 1; i <= n; i++) {
for (j = 1; j <= (2 * n - 1); j++) {
if (j == n + 1 - i || j == n - 1 + i)
printf("*");
else
printf(" ");
}
printf("\n");
}
/打印下三角/
for (i = 1; i < n; i++) {
for (j = 1; j <= (2 * n - 1); j++) {
if (j == i + 1 || j == (2 * n - 1) - i)
printf("*");
else
printf(" ");
}
printf("\n");
}
}
9.输出实心菱形

include <stdio.h>

void main() {
/n：代表菱形边长/
int i, j, n = 5;
/打印上三角/
for (i = 1; i <= n; i++) {
for (j = 1; j <= (2 * n - 1); j++) {
if (j >= n + 1 - i && j <= n - 1 + i)
printf("*");
else
printf(" ");
}
printf("\n");
}
/打印下三角/
for (i = 1; i < n; i++) {
for (j = 1; j <= (2 * n - 1); j++) {
if (j >= i + 1 && j <= (2 * n - 1) - i)
printf("*");
else
printf(" ");
}
printf("\n");
}
}