首页 > 解决方案 > 2 线程“主”java.util.NoSuchElementException 中的方法异常

问题描述

我在线程“main”java.util.NoSuchElementException 错误消息中不断收到异常。我试过换东西,但我一直有这个问题

我试过用不同的方法声明变量,但似乎没有任何效果。

import java.util.Scanner;

public class LabProgram {

    public static double drivingCost(double drivenMiles, double milesPerGallon, double dollarsPerGallon) {
        double totalCost = (drivenMiles / milesPerGallon) * dollarsPerGallon;
        return totalCost;
    }

    public static void main(String[] args) {
        double milesG;
        double dollarsG;
        Scanner scnr = new Scanner(System.in);
        milesG = scnr.nextDouble();
        dollarsG = scnr.nextDouble();
        drivingCost(10.0, milesG, dollarsG);
        milesG = scnr.nextDouble();
        dollarsG = scnr.nextDouble();
        drivingCost(50.0, milesG, dollarsG);
        milesG = scnr.nextDouble();
        dollarsG = scnr.nextDouble();
        drivingCost(400.0, milesG, dollarsG);
    }
}

问题是:

编写一个方法drivingCost(),输入参数drivenMiles、milesPerGallon 和dollarsPerGallon,返回行驶这些英里的美元成本。所有项目都是双精度型。如果使用 50 20.0 3.1599 调用该方法,则该方法返回 7.89975。

在程序中定义该方法,该程序的输入是汽车的英里/加仑和汽油美元/加仑(都是双倍的)。通过调用您的drivingCost() 方法三次,输出10 英里、50 英里和400 英里的汽油成本。输出每个小数点后两位的浮点值。

输入为:20.0 3.1599

预期产量:1.58 7.90 63.20

标签: javaexception

解决方案


import java.util.Scanner;

public class LabProgram {
   
   /* Define your method here */
   public static double drivingCost(double drivenMiles, double milesPerGallon, double dollarsPerGallon) {
      double totalCost = (dollarsPerGallon * drivenMiles / milesPerGallon);
      return totalCost;
}
   
   public static void main(String[] args) {
      /* Type your code here. */
      Scanner scnr = new Scanner(System.in);
      double milesPerGallon = scnr.nextDouble();
      double dollarsPerGallon = scnr.nextDouble();
      double drivenMiles = 1;
      System.out.printf("%.2f ", drivingCost(drivenMiles, milesPerGallon, dollarsPerGallon) * 10);
      System.out.printf("%.2f ", drivingCost(drivenMiles, milesPerGallon, dollarsPerGallon) * 50);
      System.out.printf("%.2f\n", drivingCost(drivenMiles, milesPerGallon, dollarsPerGallon) * 400);
   }
}

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