package calculator;

import java.io.*;

/*
* Main class for program execution
*/
public class Main {

private static final String INPUT_FILE = "expressions.txt";
private static final String OUTPUT_FILE = "results.txt";

// Method to parse number from string
private static Number parseNumber(String numberString) {
if (numberString.contains("+")) {
   String[] numberParams = numberString.split("\\+");
   double real = Double.parseDouble(numberParams[0]);
   double imaginary = Double.parseDouble(numberParams[1].replace("i",""));
   return new ComplexNumber(real, imaginary);
} else {
   double real = Double.parseDouble(numberString);
   return new Number(real);
}
}

// Method to calculate result of number operation
private static String calculate(Object number1, String operation, Object number2) {
double real1 = 0.0;
double imaginary1 = 0.0;
double real2 = 0.0;
double imaginary2 = 0.0;
if (number1 instanceof Number) {
   real1 = ((Number)number1).getReal();
}
if (number1 instanceof ComplexNumber) {
   imaginary1 = ((ComplexNumber)number1).getImaginary();
}
if (number2 instanceof Number) {
   real2 = ((Number)number2).getReal();
}
if (number2 instanceof ComplexNumber) {
   imaginary2 = ((ComplexNumber)number2).getImaginary();
}
double magnitude1 = (real1 * real1) + (imaginary1 * imaginary1);
double magnitude2 = (real2 * real2) + (imaginary2 * imaginary2);
if (operation.equals("+")) {
   double real = real1 + real2;
   double imaginary = imaginary1 + imaginary2;
   return new ComplexNumber(real, imaginary).toString();
} else if (operation.equals("-")) {
   double real = real1 - real2;
   double imaginary = imaginary1 - imaginary2;
   return new ComplexNumber(real, imaginary).toString();
} else if (operation.equals("*")) {
   double real = (real1 * real2) - (imaginary1 * imaginary2);
   double imaginary = (real1 * imaginary2) + (imaginary1 * real2);
   return new ComplexNumber(real, imaginary).toString();
} else if (operation.equals("/")) {
   double real = ((real1 * real2) - (imaginary1 * imaginary2)) / ((real2 * real2) + (imaginary2 * imaginary2));
   double imaginary = ((real1 * imaginary2) + (imaginary1 * real2)) / ((real2 * real2) + (imaginary2 * imaginary2));
   return new ComplexNumber(real, imaginary).toString();
} else if (operation.equals("<")) {
   if (magnitude1 < magnitude2)
   return "true";
   else
   return "false";
} else if (operation.equals(">")) {
   if (magnitude1 > magnitude

Program You are to write a program that reads a data file of numbe...