题解 | #记负均正#

import java.util.*;
public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        while (scanner.hasNextInt()) {
            int num = scanner.nextInt();
            int a, nCount = 0, pCount = 0;
            double pSum = 0;
            for (int i = 0; i < num; i++) {
                a = scanner.nextInt();
                if (a < 0) {
                    nCount++;
                } else if (a > 0) {
                    pCount++;
                    pSum += a;
                }
            }
            System.out.printf(nCount + " %.1f\n", pSum / pCount);
        }
    }
}