import java.util.StringTokenizer;

public class Complex
{ 
	private double real, imaginary;
	
	public Complex()
	{
		real=0;
		imaginary=0;
	}
	
	public Complex(double r, double i)
	{
		real = r;
		imaginary = i;
	}
		
	public String toString()
	{
		String R = "";
		String I = "";
		String r = Double.toString(real);
		String i = Double.toString(imaginary);
		int pointR = r.indexOf(".");
		int pointI = i.indexOf(".");
		int lengthR = r.length();
		int lengthI = i.length();
		
		
		// check if values are whole and cut off the ".0" part
		if (r.charAt(lengthR-1)=='0')
		{
			for (int k = 0; k < pointR; k++)
			{
				R = R + r.charAt(k);
			}
		}
		if (i.charAt(lengthI-1)=='0')
		{
			for (int k = 0; k < pointI; k++)
			{
				if (i.charAt(k) == '-')
				I = I + i.charAt(k) + " ";
				else
				I = I + i.charAt(k);
			}
		}	
		// all IFs are executed if the values are NOT whole
		// when REAL is 0 and IMAGINARY is POSITIVE
		if (R.equals("0") && imaginary > 0 && R.equals("") && I.equals(""))
		{
			String s = ("(" + "i" + ")");
			return s;
		}
		// when REAL is 0 and IMAGINARY is NEGATIVE
		if (R.equals("0") && imaginary < 0 && R.equals("") && I.equals(""))
		{
			String s = ("(" + "-" + "i" + ")");
			return s;
		}
		// when REAL is 0 and IMAGINARY is 0
		if (R.equals("0") && imaginary == 0.0 && R.equals("") && I.equals(""))
		{
			String s = ("(0)");
			return s;
		}
		// when REAL is POSITIVE and IMAGINARY is NEGATIVE
		if (real > 0.0 && imaginary < 0.0 && R.equals("") && I.equals(""))
		{
			for (int k = 0; k < (lengthI-1); k++)
			{
				I = I + i.charAt(k);
				if (i.charAt(k) == '-')
				{
					I = I + " ";
				}
			}
			String s = ("("+ r + " " + I + "i" + ")");
			return s;
		}
		// when REAL is POSITVE and IMAGINARY is 0
		if (real > 0.0 && imaginary == 0.0 && R.equals("") && I.equals(""))
		{
			String s = ("(" + R + ")");
			return s;
		}
		// when REAL is NEGATIVE and IMAGINARY is 0
		if (real < 0.0 && imaginary == 0.0 && R.equals("") && I.equals(""))
		{
			String s = ("(" + R + ")");
			return s;
		}
		// when BOTH ARE NEGATIVE
		if (real < 0.0 && imaginary < 0.0 && R.equals("") && I.equals(""))
		{
			String s = ("(" + R + " " + I + "i" + ")");
			return s;
		}
		// when REAL is NEGATIVE and IMAGINARY is POSITIVE
		if (real < 0.0 && imaginary > 0.0 && R.equals("") && I.equals(""))
		{
			String s = ("(" + r + " + " + i + "i" + ")");
			return s;
		}
		// when BOTH are POSITIVE
		if (real > 0.0 && imaginary > 0.0 && R.equals("") && I.equals(""))
		{
			String s = ("(" + r + " + " + i + "i" + ")");
			return s;
		}
		// when values ARE WHOLE
		String s = ("(" + R + " + " + I + "i" + ")");
		return s;
	
	}

	public Complex add( Complex c)
	{ 
		return new Complex (real+c.real, imaginary+c.imaginary);
	}
	
	public Complex subtract(Complex c)
	{
		return new Complex (real-c.real, imaginary-c.imaginary);
	}
	
	public Complex multiply(Complex c)
	{
		Complex C = new Complex (real*c.real - imaginary*c.imaginary, real*c.imaginary + c.real*imaginary);	
		return C;
	}
	
	public Complex divide(Complex c)
	{
		double Real = (real*c.real+imaginary*c.imaginary)/(Math.pow(c.real, 2) + Math.pow(c.imaginary, 2));
		double Imaginary = (imaginary*c.real - real*c.imaginary)/(Math.pow(c.real, 2) + Math.pow(c.imaginary, 2));
		
		return new Complex(Real, Imaginary); 		
	}


}

import java.io.*;
import java.util.StringTokenizer;

public class Calculator
{
	public static void main(String[] args)
	{
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		Complex num1, num2, result = new Complex();
		char op;
		boolean more;
		System.out.println("\n Complex number calculation program \n");
		do
		{
			num1 = readComplex(in, "Enter the 1st number you would like: ");
			num2 = readComplex(in, "Enter the 2nd number you would like: ");
			op = readChar(in, "Enter the operation to be preformed '+, -, *, or /': ", "+-*/");
			switch (op)
			{
				case '+': result = num1.add(num2);
				break;
				case '*': result = num1.multiply(num2);
				break;
				case '/': result = num1.divide(num2);
				break;
				case '-': result = num1.subtract(num2); 
			}	
			System.out.println(num1+" "+op+" "+num2+" = "+result);
			more = (readChar(in, "Want to do another calculation? (y/n): ", "yn") !='n');
		}
		while (more);
		System.out.println("\n Calculations have been completed \n");
	}
// Method to read a complex number
	public static Complex readComplex(BufferedReader in, String s)
	{
		System.out.print(s);
		double real = 0;
		double img = 0;
		boolean doit = true;
		//begins loop for user input
		while (true)
		{
			try
			{
				//reads input from user and checks for "i" for correct format
				String inp = in.readLine();
				int qwer = inp.indexOf("i");
				if (inp.indexOf("i") == -1)
				{	
					throw new IOException();
				}
				//Tokenizes the sring by using delimters which ar +,-,_,tab, newline, i
				StringTokenizer t = new StringTokenizer(inp, "+- //t/n/ri");
				//checks to see if there are tokens and store the value in double "real" 
				if (t.hasMoreTokens())
				{
					real = Double.parseDouble(t.nextToken());
				}
				else throw new IOException();
				//check if there are tokens and store value in double "img"
				if (t.hasMoreTokens())
				{
					img = Double.parseDouble(t.nextToken());
				}
				else throw new IOException();
				//if the program has no problems then set vaule of doit to true
				doit = true;
			}
			//handles the NumberFormatException
			catch (NumberFormatException e)
			{
				System.out.print ("\n Incorrect format, try again (num + numi): ");
				doit = false;
			}
			//handles the IOException
			catch (IOException e)
			{
				System.out.print ("\n Incorrect format, try again (num + numi): ");
				doit = false;
			}	
			//If no problems then it creates a complex object with real and img variables. 
			if (doit == true)
			{
				Complex c = new Complex(real, img);
				return c;
			}
		}
		
	}
// Method reads the first character of a string
	public static char readChar(BufferedReader in, String prompt, String chars)
	{
		System.out.print (prompt);
		String inp = "";
		while (true)
		{
			try
			{
				inp = in.readLine();
			}
			catch (IOException e)
			{
				System.out.println ("\n There is an Error!");
			}
				if (chars.indexOf(inp.charAt(0)) >= 0 )
				return chars.charAt(chars.indexOf(inp.charAt(0)));
				else 
				System.out.print("\nIncorrect value (use: + - / *): ");
		}
	}	
}