题解 | #记负均正II#

import java.math.BigDecimal;
import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {

    private static int actCount = 0;
    private static int posCount = 0;
    private static double sum = 0.0;

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        // 注意 hasNext 和 hasNextLine 的区别
        while (in.hasNextInt()) { // 注意 while 处理多个 case
            int a = in.nextInt();
            result(a);
        }

        print();
    }

    private static void result(int i) {
        if (i > 0) {
            actCount += 1;
            sum += i;
        } else if(i < 0) {
            posCount += 1;
        }

}

private static void print() {
        System.out.println(posCount);
        if (actCount == 0) {
            System.out.print(0.0);
        } else {
            double d = sum / 1.0 / actCount;
            BigDecimal bigDecimal = new BigDecimal(d);
            d = bigDecimal.setScale(1, BigDecimal.ROUND_HALF_UP).doubleValue();
            System.out.print(d);
        }
    }
}