Question

The program calculates a tax rate and tax to pay given an annual salary. The program uses a class, TaxTableTools, which has the tax table built in. Run the program with annual salaries of 10000, 50000, 50001, 100001 and -1 (to end the program) and note the output tax rate and tax to pay.

The output should be as follows:

Enter annual salary (-1 to exit):

10000

Annual Salary: 10000 Tax rate: 0.1 Tax to pay: 1000

Enter annual salary (-1 to exit):

50000

Annual Salary: 50000 Tax rate: 0.2 Tax to pay: 10000

Enter annual salary (-1 to exit):

50001

Annual Salary: 50001 Tax rate: 0.3 Tax to pay: 15000

Enter annual salary (-1 to exit):

100001

Annual Salary: 100001 Tax rate: 0.4 Tax to pay: 40000

Enter annual salary (-1 to exit): -1

1. Overload the constructor.

2. Add to the TaxTableTools class an overloaded constructor that accepts the base salary table and corresponding tax rate table as parameters.

3. Modify the main function to call the overloaded constructor with the two tables (vectors) provided in the main function. Be sure to set the nEntries value, too.

4. Note that the tables in the main function are different than the tables in the TaxTableTools class.

The updated output should be as follows:

Enter annual salary (-1 to exit):

10000

Annual Salary: 10000 Tax rate: 0.2 Tax to pay: 2000

Enter annual salary (-1 to exit):

50000

Annual Salary: 50000 Tax rate: 0.6 Tax to pay: 30000

Enter annual salary (-1 to exit):

50001

Annual Salary: 50001 Tax rate: 0.6 Tax to pay: 30000

Enter annual salary (-1 to exit):

1000001

Annual Salary: 1000001 Tax rate: 0.8 Tax to pay: 800000

Enter annual salary (-1 to exit): -1

main.cpp

#include
#include
#include
#include
#include "TaxTableTools.h"
#include "TaxTableTools.cpp"
using namespace std;

int main() {
const string PROMPT_SALARY = "\nEnter annual salary (-1 to exit)";
int annualSalary;
double taxRate;
int taxToPay;
vector salaryBase(5);
vector taxBase(5);

salaryBase.at(0) = 0;
salaryBase.at(1) = 10000;
salaryBase.at(2) = 40000;
salaryBase.at(3) = 80000;
salaryBase.at(4) = numeric_limits::max();

taxBase.at(0) = 0.0;
taxBase.at(1) = 0.20;
taxBase.at(2) = 0.40;
taxBase.at(3) = 0.60;
taxBase.at(4) = 0.80;

// FIXME: Use the overloaded constructor with the two tables.
TaxTableTools table;

// Get the first annual salary to process
annualSalary = table.GetInteger(PROMPT_SALARY);

while(annualSalary >= 0) {
taxRate = table.GetValue(annualSalary);
taxToPay = static_cast(annualSalary * taxRate); // Truncate tax to an integer amount
cout << "Annual Salary: " << annualSalary <<
"\tTax rate: " << taxRate <<
"\tTax to pay: " << taxToPay << endl;

// Get the next annual salary
annualSalary = table.GetInteger(PROMPT_SALARY);
}

return 0;
}

TaxTableTools.cpp

#include
#include
#include
#include "TaxTableTools.h"
using namespace std;

// Default constructor
TaxTableTools::TaxTableTools() {
search.push_back(0);
search.push_back(20000);
search.push_back(50000);
search.push_back(100000);
search.push_back(numeric_limits::max());
value.push_back(0.0);
value.push_back(0.10);
value.push_back(0.20);
value.push_back(0.30);
value.push_back(0.40);
nEntries = search.size(); // Set the length of the search table
}

// *************************************************************************

// Overloaded constructor

// FIXME: Add an overloaded constructor to load the search and value tables.
// FIXME: Be sure to set the nEntries value, too.
// Hint: Don't forget to change the header file too.

// **************************************************************************

// Function to prompt for and input an integer
int TaxTableTools::GetInteger(const string userPompt) {
int inputValue;

cout << userPompt << ": " << endl;
cin >> inputValue;

return inputValue;
}

// **************************************************************************

// Function to get a value from one table based on a range in the other table

double TaxTableTools::GetValue(int searchArgument) {
double result;
bool keepLooking;
int i;

keepLooking = true;
i = 0;

while ((i < nEntries) && keepLooking) {
if (searchArgument <= search[i]) {
result = value[i];
keepLooking = false;
}
else {
++i;
}
}

return result;
}

TaxTableTools.h

#ifndef TAXTABLETOOLS_H
#define TAXTABLETOOLS_H

#include
#include
#include
using namespace std;

class TaxTableTools {
public:
TaxTableTools();
double GetValue(int searchArgument);
int GetInteger(const string userPompt);
private:
vector search;
vector value;
int nEntries;
};

#endif

Answer 1

TaxTableTools.h

#ifndef TAXTABLETOOLS_H
#define TAXTABLETOOLS_H
#include<vector>

using namespace std;

class TaxTableTools {
   public:
       TaxTableTools();
       TaxTableTools(vector<int> search, vector<float> value);
       double GetValue(int searchArgument);
       int GetInteger(const string userPompt);
   private:
       vector<int> search;
       vector<float> value;
       int nEntries;
};

#endif

TaxTableTools.cpp

#include<vector>
#include<limits>
#include "TaxTableTools.h"
using namespace std;

TaxTableTools::TaxTableTools() {
   search.push_back(0);
   search.push_back(20000);
   search.push_back(50000);
   search.push_back(100000);
   search.push_back(std::numeric_limits<int>::max());
   value.push_back(0.0);
   value.push_back(0.10);
   value.push_back(0.20);
   value.push_back(0.30);
   value.push_back(0.40);
   nEntries = search.size();
}

/**
   overloaded constructor
   @params:   vector<int> search : contains search value for base salary
               vector<float> value : contains tax rate on corresponding base salary
   @compute:    set search vector and value vector and nEntries of this object
**/
TaxTableTools::TaxTableTools(vector<int> search, vector<float> value)
{
   for(int i=0; i<search.size(); i++)
   {
       this->search.push_back(search[i]);
   }
   for(int i=0; i<value.size(); i++)
   {
       this->value.push_back(value[i]);
   }
   nEntries=this->search.size();
}

int TaxTableTools::GetInteger(const string userPompt) {
   int inputValue;
   cout << userPompt << ": " << endl;
   cin >> inputValue;
   return inputValue;
}

double TaxTableTools::GetValue(int searchArgument) {
   double result;
   bool keepLooking;
   int i;

   keepLooking = true;
   i = 0;

   while ((i < nEntries) && keepLooking)
   {
       if (searchArgument <= search[i])
       {
           result = value[i];
           keepLooking = false;
       }
       else
       {
           ++i;
       }
   }

   return result;
}

main.cpp

#include<iostream>
#include<vector>
#include<limits>
#include "TaxTableTools.h"
#include "TaxTableTools.cpp"
using namespace std;

int main() {
   const string PROMPT_SALARY = "\nEnter annual salary (-1 to exit)";
   int annualSalary;
   double taxRate;
   int taxToPay;
   vector<int> salaryBase(5);
   vector<float> taxBase(5);

   salaryBase.at(0) = 0;
   salaryBase.at(1) = 10000;
   salaryBase.at(2) = 40000;
   salaryBase.at(3) = 80000;
   salaryBase.at(4) = numeric_limits<int>::max();

   taxBase.at(0) = 0.0;
   taxBase.at(1) = 0.20;
   taxBase.at(2) = 0.40;
   taxBase.at(3) = 0.60;
   taxBase.at(4) = 0.80;

   TaxTableTools table(salaryBase, taxBase);
   annualSalary = table.GetInteger(PROMPT_SALARY);

   while(annualSalary >= 0) {
       taxRate = table.GetValue(annualSalary);
       taxToPay = static_cast<int>(annualSalary * taxRate);
       cout << "Annual Salary: " << annualSalary <<
       "\tTax rate: " << taxRate <<
       "\tTax to pay: " << taxToPay << endl;

       annualSalary = table.GetInteger(PROMPT_SALARY);
   }

   return 0;
}