基本计算器帮助Java

Question

我正在尝试为我的学校项目创建一个计算器，但是由于某种原因，当我尝试进行编译时，它表示我有问题，而且不知道如何解决它。 我在此部分收到错误“此行有多个标记-本地变量inputA可能尚未初始化-本地变量inputB可能尚未初始化”：

     atimesb = (inputA * inputB);
     adividedbyb = (inputA / inputB);
     aplusb = (inputA + inputB);
     aminusb = (inputA - inputB);

是错的。

import java.util.Scanner;
public class Calculator {

    public static void main(String[] args) {

         int inputA;
         int inputB;
         int atimesb;
         int adividedbyb;
         int aplusb;
         int aminusb;
         atimesb = (inputA * inputB);
         adividedbyb = (inputA / inputB);
         aplusb = (inputA + inputB);
         aminusb = (inputA - inputB);

         String operation;

         Scanner in = new Scanner(System.in);  

         System.out.println("Enter the first number");  
         inputA = in.nextInt();  

         System.out.println("Enter the operation"); 
         operation = in.next();

         System.out.println("Enter the second number");  
         inputB = in.nextInt();  



         if (operation.equals ("+"))
         {
             System.out.println(inputA + " + " + inputB + "=" + aplusb);
         }
         if (operation.equals ("-"))
         {
             System.out.println(inputA + " - " + inputB + "=" + aminusb);
         }
         if (operation.equals ("/"))
         {
             System.out.println(inputA + " / " + inputB + "=" + adividedbyb);
         }
         if (operation.equals ("*"))
         {
             System.out.println(inputA + " * " + inputB + "=" + atimesb);
         }
         if (operation.equals ("add"))
         {
             System.out.println(inputA + " * " + inputB + "=" + aplusb);
         }
         if (operation.equals ("subtract"))
         {
             System.out.println(inputA + " - " + inputB + "=" + aminusb);
         }
         if (operation.equals ("divide"))
         {
             System.out.println(inputA + " / " + inputB + "=" + adividedbyb);
         }
         if (operation.equals ("multiply"))
         {
             System.out.println(inputA + " * " + inputB + "=" + atimesb);
         }


}
}

如果有人可以帮助我，我将非常感激。

Answer 1

您需要先读取这些值，然后再使用它们。 像这样：

     System.out.println("Enter the first number");  
     inputA = in.nextInt();  

     System.out.println("Enter the operation"); 
     operation = in.next();

     System.out.println("Enter the second number");  
     inputB = in.nextInt();  

     atimesb = (inputA * inputB);
     adividedbyb = (inputA / inputB);
     aplusb = (inputA + inputB);
     aminusb = (inputA - inputB);