Question

我是BSIT大学一年级编程的新手，我们的任务是编写一个SimpleArithmetic，它会首先询问你的名字，然后你会被要求输入第一个和第二个整数。

在给出要求之后它必须显示“你好（输入的名字）”然后接下来的是两个整数的总和，差异，产品和模型，最后它将显示“谢谢你！”。

我尝试了很多代码，但我不会跑，所以有人能帮助我吗？我真的很感激，因为我真的很想知道会发生什么。

这是我的代码

public class SimpleArithmetic{

    public static void main(String[] args){

    //1: Declare name as symbol
    //2: num 1, num 2, sum, difference, product, mod to 0;

    System.out.print("Enter your name: ");
    name = in.next();    // <---- HERE
    System.out.printf("\nEnter first integer: ");
    System.out.printf("\nEnter second integer: ");
    System.out.printf("\nnum 1 + num 2");
    System.out.printf("\nnum 1 - num 2");
    System.out.printf("\nnum 1 * num 2");
    System.out.printf("\nnum 1 % num 2");
    System.out.print("Hello \n + name");
    System.out.println("num 1" + "+" + "is" + "sum");
    System.out.println("num 1" + "-" + "is" + "difference");
    System.out.println("num 1" + "*" + "is" + "product");
    System.out.println("num 1" + "%" + "is" + "mod");
    System.out.print("Thank You!");
    }

}

当我尝试编译java文件时，粗体是错误

Answer 1

使用以下类扫描仪读取输入：

Scanner scanner = new Scanner(System.in);  // Init scanner
String name = scanner.nextLine();          // Reads a full line
int a = scanner.nextInt();                 // Reads one integer
int b = scanner.nextInt();                 // Reads another integer

如果您想了解有关课程Scanner的更多信息，请查看文档here。

基本上，在这种情况下，扫描程序是一个从流（System.in）读取输入的有用类。来自javadoc

一个简单的文本扫描程序，可以解析基本类型和字符串使用正则表达式。

Answer 2

以下内容适用于您......

package com.test;

import java.io.BufferedReader;
import java.io.InputStreamReader;

public class SimpleArithmetic{

public static void main(String[] args){
    try{
        //1: Declare name as symbol
        //2: num 1, num 2, sum, difference, product, mod to 0;

        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));

        System.out.print("Enter your name: ");
        String name = in.readLine();   // <---- HERE
        System.out.printf("\nEnter first integer: ");
        String str1 = in.readLine();
        int number1 = Integer.parseInt(str1);
        System.out.printf("\nEnter second integer: ");
        String str2 = in.readLine();
        int number2 = Integer.parseInt(str2);
        System.out.print("Hello \n "+ name);
        System.out.println("num 1" + "+" + "is" + (number1 + number2));
        System.out.println("num 1" + "-" + "is" + (number1 - number2));
        System.out.println("num 1" + "*" + "is" + (number1 * number2));
        System.out.println("num 1" + "%" + "is" + (number1 % number2));
        System.out.print("Thank You!");
    }catch(Exception e)
    {
        e.printStackTrace();
    }
}

}

Answer 3

删除变量上的所有双qoutes。

将System.out.print("Hello \n + name");更改为 System.out.print("Hello \n + name);

System.out.println("num 1" + "+" + "is" + "sum");至System.out.println("num 1" + "+" + "is" + sum);

System.out.println("num 1" + "-" + "is" + "difference"); to  `System.out.println("num 1" + "-" + "is" + difference);`

System.out.println("num 1" + "*" + "is" + "product");至System.out.println("num 1" + "*" + "is" + product);

System.out.println("num 1" + "%" + "is" + "mod"); to `System.out.println("num 1" + "%" + "is" + mod);`

Answer 4

使用Scanner并尝试catch块：

分配注释中没有列出变量声明。

你应该做类似的事情：

import java.util.Scanner;

public class SimpleArithmetic {

    int num1 = 0, num2 = 0, sum = 0, difference = 0, product = 0, mod = 0;
    String name = null;
    Scanner in = null;

    public static void main(String[] args) {
        SimpleArithmetic sa = new SimpleArithmetic();

        try {
            sa.doSimpleArithmetic();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    void doSimpleArithmetic() throws Exception {
        in = new Scanner(System.in);
        System.out.print("Enter your name: ");
        name = in.nextLine();

        System.out.printf("\nEnter first integer: ");
        num1 = Integer.parseInt(in.nextLine());
        System.out.printf("\nEnter second integer: ");
        num2 = Integer.parseInt(in.nextLine());

        sum = num1 + num2;
        difference = num1 - num2;
        product = num1 * num2;
        mod = num1 / num2;

        System.out.println("\n" + "Hello " + name + "\n");

        System.out.println(num1 + " + " + num2 + " is :" + sum);
        System.out.println(num1 + " - " + num2 + " is :" + difference);
        System.out.println(num1 + " * " + num2 + " is :" + product);
        System.out.println(num1 + " % " + num2 + " is :" + mod);

        System.out.println("\n" + "Thank You!");
        in.close();
    }
}

Answer 5

$ec2 = new Aws\Ec2\Ec2Client([credentials]);

$result = $ec2->runInstances(array(
                'DryRun' => false,
                // ImageId is required
                'ImageId' => '[removed]',
                // MinCount is required
                'MinCount' => 1,
                // MaxCount is required
                'MaxCount' => 1,
                'KeyName' => '[removed]',
                'SecurityGroupIds' => array('[removed]'),

                'InstanceType' => 'r3.4xlarge',

                'Placement' => array(
                    'AvailabilityZone' => 'us-east-1a',

                ),
                'EbsOptimized' => false,
                'Monitoring' => array(
                    // Enabled is required
                    'Enabled' => true,
                ),

            ));

$arr = $result->toArray();

$instanceId = $arr['Instances'][0]['InstanceId'];

echo 'created instance '.$instanceId."\n";

$ec2->waitUntil('InstanceRunning', ['InstanceIds' => array($instanceId)]);          

$result = $ec2->describeInstances(array(
                'InstanceIds' => array($instanceId),
            ));
$dnsName = current($result->getPath('Reservations/*/Instances/*/PublicDnsName'));

简单算术代码

5 个答案: