题解 | 记负均正

#include <iostream>
#include <vector>
using namespace std;

int main() {
    int a;

    while (cin >> a) {
        int num;
        int navCount = 0, posCount = 0;
        double  posSum = 0;
        for (int i = 0; i < a; i++) {
            cin >> num;
            if (num < 0)
                navCount++;
            else if (num > 0) {
                posCount++;
                posSum += num;
            }
        }

        double agv = posSum == 0 ? 0 : posSum  / posCount ;
        cout << navCount << " ";
        cout << agv << endl;
    }

    return 0;
}