没有堆栈或arraylist的java计算器
答案 0 :(得分：1)
我可能会尝试编写一个类似String simplify ( String expression )的方法来获取表达式字符串（例如，“3 ^（2 *（4-2））”并应用PEMDAS来确定下一个操作，评估它，并返回简化表达式。
所以，
3^(2*(4-2))...
3^(2*2)...
3^(4)...
81
完成后，您可以在while循环中调用它，直到输出为简单数字。
simplify会有一些编码，但毕竟是一个家庭作业，我认为它只能用你列出的元素编写（Double，String， StringTokenizer等。）
答案 1 :(得分：0)
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);
}
}