不带堆栈或数组列表的java计算器

没有堆栈或arraylist的java calculator

我可能会尝试编写一个类似

字符串简化（字符串表达式）

的方法，该方法将获取一个表达式字符串（例如，“3^（2*（4-2）），并应用p.e.M.d.a.S.来确定下一个操作，对其求值，然后返回简化的表达式

所以

一旦有了它，就可以在

while

循环中调用它，直到输出为一个简单的数字

---

simplify

将是一个相当多的编码，但它毕竟是一个家庭作业，我认为它只能使用您列出的元素（Double、String、StringTokenizer等）编写

这是一个家庭作业吗？也许这取决于你在解析什么，但我不认为将自己限制为5个操作数是一件好事。什么是一些示例输入？它会像

1+2

还是

1+2+

？你说“不允许使用堆栈或数组列表”。这是否意味着您需要实现自己的堆栈？这是否意味着您需要编写递归方法？（即，隐式使用调用堆栈作为数据堆栈）如果以上两项都没有，那么你可以做什么？你不能在没有某种堆栈的情况下计算任意的括号表达式。实际上这不是一个家庭作业，而是一本书中包含的一个示例。我的任务是尝试其中一个示例，我选择了这个。你能解释一下这是什么吗？

 3^(2*(4-2))...
 3^(2*2)...
 3^(4)...
 81

 import java.io.*;
import java.lang.*;
import javax.swing.JOptionPane;
class calculator
{
   public static void main(String args[])throws IOException
   {
       InputStreamReader isr = new InputStreamReader(System.in);
       BufferedReader br = new BufferedReader(isr);
       calculator otp = new calculator();
       String choice1 = JOptionPane.showInputDialog("Mathematical operations list:-\n1.Addition\n2.Subtraction\n3.Multiplication\n4.Division\n5.Modulus\n6.Square Root\n7.Exponent\n8.Pi\n9.Sine\n10.Cosine\n11.Tangent\nEnter the number of the mathematical operation of your choice");
       int choice = Integer.parseInt(choice1);
       if( choice == 1)
       {
           otp.Addition();
       }
       else if( choice == 2)
       {
           otp.Subtraction();
       }
       else if( choice == 3)
       {
           otp.Multiplication();
       }
       else if( choice == 4)
       {
           otp.Division();
       }
       else if( choice == 5)
       {
           otp.Modulus();
       }
       else if( choice == 6)
       {
           otp.Squareroot();
       }
       else if( choice == 7)
       {
           otp.Exponent();
       }
       else if( choice == 8)
       {
           otp.Pi();
       }
       else if( choice == 9)
       {
           otp.Sine();
       }
       else if( choice == 10)
       {
           otp.Cosine();
       }
       else if( choice == 11)
       {
           otp.Tangent();
       }
       else
       {
           JOptionPane.showMessageDialog(null, "Enter a number between 1 and 11 ","Info",JOptionPane.INFORMATION_MESSAGE);
       }
   }
   public void Squareroot()throws IOException
   {
       InputStreamReader isr = new InputStreamReader(System.in);
       BufferedReader br = new BufferedReader(isr);
       String sqrt1;
       sqrt1 = JOptionPane.showInputDialog("Enter the number");
       double sqrt = Double.parseDouble(sqrt1);
       double ans = Math.sqrt(sqrt);
       JOptionPane.showMessageDialog(null, "Answer: " + ans,"Answer",JOptionPane.INFORMATION_MESSAGE);
   }
   public void Addition()throws IOException
   {
       InputStreamReader isr = new InputStreamReader(System.in);
       BufferedReader br = new BufferedReader(isr);
       String add11, add21;
       add11 = JOptionPane.showInputDialog("Enter the first number");
       add21 = JOptionPane.showInputDialog("Enter the second number");
       double add1 = Double.parseDouble(add11);
       double add2 = Double.parseDouble(add21);
       double ans = add1 + add2;
       JOptionPane.showMessageDialog(null, "Answer: " + ans,"Answer",JOptionPane.INFORMATION_MESSAGE);
   }
   public void Subtraction()throws IOException
   {
       InputStreamReader isr = new InputStreamReader(System.in);
       BufferedReader br = new BufferedReader(isr);
       String sub11, sub21;
       sub11 = JOptionPane.showInputDialog("Enter the first number");
       sub21 = JOptionPane.showInputDialog("Enter the second number");
       double sub1 = Double.parseDouble(sub11);
       double sub2 = Double.parseDouble(sub21);
       double ans = sub1 - sub2;
       double rev = sub2 - sub1;
       JOptionPane.showMessageDialog(null, "Answer: " + ans,"Answer",JOptionPane.INFORMATION_MESSAGE);
       JOptionPane.showMessageDialog(null, "Reverse Answer: " + rev,"Reverse Answer",JOptionPane.INFORMATION_MESSAGE);
   }
   public void Multiplication()throws IOException
   {
       InputStreamReader isr = new InputStreamReader(System.in);
       BufferedReader br = new BufferedReader(isr);
       String mul11, mul21;
       mul11 = JOptionPane.showInputDialog("Enter the first number");
       mul21 = JOptionPane.showInputDialog("Enter the second number");
       double mul1 = Double.parseDouble(mul11);
       double mul2 = Double.parseDouble(mul21);
       double ans = mul1 * mul2;
       JOptionPane.showMessageDialog(null, "Answer: " + ans,"Answer",JOptionPane.INFORMATION_MESSAGE);
   }
   public void Division()throws IOException
   {
       InputStreamReader isr = new InputStreamReader(System.in);
       BufferedReader br = new BufferedReader(isr);
       String div11, div21;
       div11 = JOptionPane.showInputDialog("Enter the first number");
       div21 = JOptionPane.showInputDialog("Enter the second number");
       double div1 = Double.parseDouble(div11);
       double div2 = Double.parseDouble(div21);
       double ans = div1 / div2;
       double rev = div2 / div1;
       JOptionPane.showMessageDialog(null, "Answer: " + ans,"Answer",JOptionPane.INFORMATION_MESSAGE);
       JOptionPane.showMessageDialog(null, "Reverse Answer: " + rev,"Reverse Answer",JOptionPane.INFORMATION_MESSAGE);
   }
   public void Modulus()throws IOException
   {
       InputStreamReader isr = new InputStreamReader(System.in);
       BufferedReader br = new BufferedReader(isr);
       String mod11, mod21;
       mod11 = JOptionPane.showInputDialog("Enter the first number");
       mod21 = JOptionPane.showInputDialog("Enter the second number");
       double mod1 = Double.parseDouble(mod11);
       double mod2 = Double.parseDouble(mod21);
       double ans = mod1 % mod2;
       double rev = mod2 % mod1;
       JOptionPane.showMessageDialog(null, "Answer: " + ans,"Answer",JOptionPane.INFORMATION_MESSAGE);
       JOptionPane.showMessageDialog(null, "Reverse Answer: " + rev,"Reverse Answer",JOptionPane.INFORMATION_MESSAGE);
   }
   public void Exponent()throws IOException
   {
       InputStreamReader isr = new InputStreamReader(System.in);
       BufferedReader br = new BufferedReader(isr);
       String exp11, exp21;
       exp11 = JOptionPane.showInputDialog("Enter the base number");
       exp21 = JOptionPane.showInputDialog("Enter the power number");
       double exp1 = Double.parseDouble(exp11);
       double exp2 = Double.parseDouble(exp21);
       double ans = Math.pow(exp1 , exp2);
       JOptionPane.showMessageDialog(null, "Answer: " + ans,"Answer",JOptionPane.INFORMATION_MESSAGE);
   }
   public void Sine()throws IOException
   {
       InputStreamReader isr = new InputStreamReader(System.in);
       BufferedReader br = new BufferedReader(isr);
       String sin1;
       sin1 = JOptionPane.showInputDialog("Enter the number");
       double sin = Double.parseDouble(sin1);
       double ans = Math.sin(sin);
       JOptionPane.showMessageDialog(null, "Answer: " + ans,"Answer",JOptionPane.INFORMATION_MESSAGE);
   }
   public void Cosine()throws IOException
   {
       InputStreamReader isr = new InputStreamReader(System.in);
       BufferedReader br = new BufferedReader(isr);
       String cos1;
       cos1 = JOptionPane.showInputDialog("Enter the number");
       double cos = Double.parseDouble(cos1);
       double ans = Math.cos(cos);
       JOptionPane.showMessageDialog(null, "Answer: " + ans,"Answer",JOptionPane.INFORMATION_MESSAGE);
   }
   public void Tangent()throws IOException
   {
       InputStreamReader isr = new InputStreamReader(System.in);
       BufferedReader br = new BufferedReader(isr);
       String tan1;
       tan1 = JOptionPane.showInputDialog("Enter the number");
       double tan = Double.parseDouble(tan1);
       double ans = Math.tan(tan);
       JOptionPane.showMessageDialog(null, "Answer: " + ans,"Answer",JOptionPane.INFORMATION_MESSAGE);
   }
    public void Pi()throws IOException
   {
       InputStreamReader isr = new InputStreamReader(System.in);
       BufferedReader br = new BufferedReader(isr);
       String pi1;
       pi1 = JOptionPane.showInputDialog("Enter the number");
       double pi = Double.parseDouble(pi1);
       double ans = Math.PI * pi;
       JOptionPane.showMessageDialog(null, "Answer: " + ans,"Answer",JOptionPane.INFORMATION_MESSAGE);
   }
}