Question

import java.util.Scanner;

public class InputCalculator {
    public static void inputThenPrintSumAndAverage(){
        Scanner scanner = new Scanner(System.in);

        boolean first = true;

        int sum = 0;
        int count = 0;
        int avg = 0;
        while(true){
            int number = scanner.nextInt();
            boolean isAnInt = scanner.hasNextInt();

            if(isAnInt){
                sum += number;
                count++;
                avg = Math.round((sum)/count);
            }else{
                System.out.println("SUM = " + sum + " AVG = " + avg);
                break;
            }
            scanner.nextLine();
        }
        scanner.close();
    }
}

当输入为“ 1、2、3、4、5，a”时，我认为它不是在读取输入5，结果总和= 10且avg = 2！为什么会这样呢？顺便说一下，这只是一种方法，而不是整个代码！

Answer 1

当scanner.nextInt（）为您提供“ 5”时，下一行“ scanner.hasNextInt（）为假”。只需更改订单顺序

import java.util.Scanner;

public class InputCalculator {
    public static void inputThenPrintSumAndAverage(){
        Scanner scanner = new Scanner(System.in);

        boolean first = true;

        int sum = 0;
        int count = 0;
        int avg = 0;

        while(true){
            boolean isAnInt = scanner.hasNextInt();

            if(isAnInt){
                int number = scanner.nextInt();
                sum += number;
                count++;
                avg = Math.round((sum)/count);
            }else{
                System.out.println("SUM = " + sum + " AVG = " + avg);
                break;
            }
            scanner.nextLine();
        }
        scanner.close();
    }
}

您还可以像清除代码一样

import java.util.Scanner;

public class InputCalculator {
    public static void inputThenPrintSumAndAverage(){
        Scanner scanner = new Scanner(System.in);

        int sum = 0;
        int count = 0;

        while( scanner.hasNextInt() ){
            int number = scanner.nextInt();
            sum += number;
            count++;
        }
        
        scanner.close();

        double avg = Math.round((sum)/count);
        System.out.println("SUM = " + sum + " AVG = " + avg); 
    }
}

这种方法有什么问题...？

1 个答案: