输入十进制和四舍五入到最近整数的简单Java方法

Question

我正在使用Java SDK进行编译。需要我说的是，我是个初学者。这是我试图用来"要求用户输入十进制，代码应该输出一个整数"的代码

import java.util.*;
public class readDecimal {
    public static void main(String args[]) {
        Scanner input = new Scanner(System.in);
        double decimalNumber;
        long intNumber;
        System.out.println(“Please enter a decimal number:“);
        decimalNumber = input.nextDouble();
        intNumber = Math.round(decimalNumber);
        System.out.println(decimalNumber +
                “ rounded to the nearest integer is “ + intNumber);
    }
}

我做错了什么？我看到了其他帖子，但对于初学者来说，它们似乎太复杂了。你能帮忙吗？非常感谢。Diane

Answer 1

您的引号不正确；出于某种原因，它们是unicode。通过在System.out.println语句中手动键入来替换所有引号。

  public static void main(String args[]) {
    Scanner input = new Scanner(System.in);
    double decimalNumber;
    long intNumber;
    System.out.println("Please enter a decimal number:");
    decimalNumber = input.nextDouble();
    intNumber = Math.round(decimalNumber);
    System.out.println(decimalNumber +
            " rounded to the nearest integer is " + intNumber);
}

Answer 2

您可以使用Math.round方法对双数进行四舍五入。

import java.util.*;
public class RoundingDecimal {
    public static void main(String args[]) {
        Scanner sc = new Scanner(System.in);
        double num1;
        double num2;
        System.out.print("Please enter a decimal number: ");
        num1 = sc.nextDouble();
        num2 = Math.round(num1);
        System.out.println(" Rounded to the nearest integer is " + num2);    
    }
}