java - 扫描仪仅读取第一行

Question

import java.util.Scanner;

public class ArithmeticDemo {
    public static void main(String[] args)
    {
        int firstNumber;
        int secondNumber;
        int sum;
        int difference;
        int average;
        Scanner input = new Scanner(System.in);
        System.out.print("Please enter a double >> 14");
        firstNumber = input.nextInt();
        System.out.print("Please enter another double >> 11 ");
        secondNumber = input.nextInt();
        sum = firstNumber + secondNumber;
        difference = firstNumber - secondNumber;
        average = sum / 2;
        System.out.println(firstNumber + " + " + secondNumber + " is " + sum);
        System.out.println(firstNumber + " - " + secondNumber + " is " + difference);
        System.out.println("The average of " + firstNumber + " and " + secondNumber + " is " + average);
    }
}

我正在做学校作业，乍一看一切似乎都很好，我什至休息了一下然后回来，但代码应该在执行时显示

Please enter an integer >> 14
Please enter another integer >> 11
14 + 11 is 25
14 - 11 is 3
The average of 14 and 11 is 12

但是当我执行它时，它只读取

Please enter an integer >> 14

我正在使用 Eclipse，它统计我的扫描仪输入命令有问题，但我不确定它是什么，感谢您的帮助。

Answer 1

您的打印语句不应包含那里的数字。它应该只读取“System.out.print(“请输入 double >>”)”。这是第一个问题。此外，您的提示显示“请输入 double ”，但您正在读取一个整数。将该行更改为 input.nextDouble()。否则，它会完全按预期运行。它打印“请输入 double >>”，我输入一个数字，它打印下一行，我输入另一个数字，它输出信息。查看 java.util.Scanner 的文档 here