题解 | #记负均正#

#include <stdio.h>

int main() {
    int n;
    int num[2000];
    scanf("%d", &n);
    for (int i = 0; i < n; i++) {
        scanf("%d", &num[i]);
    }
    int negativeNum = 0; //如果不初始化，会得到错误结果
    for (int i = 0; i < n; i++) {
        if (num[i] < 0) {
            negativeNum++;
        }
    }

    float positiveNumAverage;
    int positiveNum = 0;
    int total = 0;
    for (int i = 0; i < n; i++) {
        if (num[i] > 0) {
            total += num[i];
            positiveNum++;
        }
    }
    if (positiveNum != 0) {
        positiveNumAverage = (float)total / positiveNum; //注意这里的类型转换，否则向下取整得不到正确结果
    } else {
        positiveNumAverage = 0;
    }

    printf("%d %.1f", negativeNum, positiveNumAverage);

    return 0;
}