编写c程序，.输入20个有符号整数，统计正整数、零、负整数的个数。

#include <stdio.h>

int main() {
    int num, positive = 0, zero = 0, negative = 0;
    for(int i = 0; i < 20; i++) {
        scanf("%d", &num);
        if(num > 0) positive++;
        else if(num == 0) zero++;
        else negative++;
    }
    printf("正整数个数：%d\n零的个数：%d\n负整数个数：%d\n", positive, zero, negative);
    return 0;
}