用c语言编写程序，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, pos_num = 0, zero_num = 0, neg_num = 0;
    for (int i = 0; i < 20; i++) {
        printf("请输入第%d个整数：", i+1);
        scanf("%d", &num);
        if (num > 0) {
            pos_num++;
        } else if (num == 0) {
            zero_num++;
        } else {
            neg_num++;
        }
    }
    printf("正整数个数：%d\n", pos_num);
    printf("零的个数：%d\n", zero_num);
    printf("负整数个数：%d\n", neg_num);
    return 0;
}