以下是一个用C语言实现输出字符菱形的示例程序：
#include <stdio.h>
int main() {
int n, c, k, space = 1;
printf("Enter number of rows: ");
scanf("%d", &n);
space = n - 1;
for (k = 1; k <= n; k++) {
for (c = 1; c <= space; c++)
printf(" ");
space--;
for (c = 1; c <= 2*k-1; c++)
printf("*");
printf("\n");
}
space = 1;
for (k = 1; k <= n - 1; k++) {
for (c = 1; c <= space; c++)
printf(" ");
space++;
for (c = 1 ; c <= 2*(n-k)-1; c++)
printf("*");
printf("\n");
}
return 0;
}
该程序会要求用户输入行数，然后输出一个以星号（*）组成的菱形。如果想输出其他字符菱形，只需将 printf("*") 替换为 printf("你想要的字符") 即可。
