Question

I need assistance with the C++ code below to remove the "this" pointers while maintaining the code's current output and functionality. Also, there should be a private class in the header file, but I'm not sure what I should include there. Any help would be greatly appreciated!

***main.cpp driver file***

#include <iostream>

#include "vector.h"

using namespace std;

int main()

{

  vectorInfo v1(7, 6);

  vectorInfo v2(5, 4);

   

  v1.set(3, 2);

  cout << "v1 : ";

  v1.print();

   

  cout << "v2 : ";

  v2.print();

   

  cout << "v1 magnitude : " << v1.magnitude() << endl;

  cout << "v1 direction : " << v1.direction() << " radians" << endl;

   

  cout << "v1 + v2 : ";

  (v1 + v2).print();

   

  cout << "v1 - v2 : ";

  (v1 - v2).print();

   

  cout << "v1 * v2 : " << v1 * v2 << endl;

   

  cout << "v1 == v2 : " << (v1 == v2) << endl;

}

***vector.cpp file***

#include "vector.h"

vectorInfo::vectorInfo()

{

  this->x = 0;

  this->y = 0;

}

vectorInfo::vectorInfo(int x, int y)

{

  this->x = x;

  this->y = y;

}

void vectorInfo::set(int x, int y)

{

  this->x = x;

  this->y = y;

}

double vectorInfo::magnitude()

{

  return sqrt(x * x + y * y);

}

double vectorInfo::direction()

{

  return atan(y / x);

  //can also use atan2(y, x) which is prefered, you can read about atan2 here : http://www.cplusplus.com/reference/cmath/atan2/

}

void vectorInfo::print()

{

  cout << x << " " << y << endl;

}

vectorInfo vectorInfo::operator-(vectorInfo const& b)

{

  return vectorInfo(this->x - b.x, this->y - b.y);

}

double vectorInfo::operator*(vectorInfo const& b)

{

  return this->x * b.x + this->y * b.y;

}

vectorInfo operator+(vectorInfo const& a, vectorInfo const& b)

{

  return vectorInfo(a.x + b.x, a.y + b.y);

}

bool operator==(vectorInfo const& a, vectorInfo const& b)

{

  return a.x == b.x && a.y == b.y;

}

***vector.h header file***

#include <iostream>

#include <cmath>

using namespace std;

class vectorInfo

{

  public:

    double x;

    double y;

   

    vectorInfo();

    vectorInfo(int x, int y);

   

    // member functions

    void set(int x, int y);

    double magnitude();

    double direction();

    void print();

   

    // member operators

    vectorInfo operator-(vectorInfo const& b);

    double operator*(vectorInfo const& b);

   

    // non member operators

    friend vectorInfo operator+(vectorInfo const& a, vectorInfo const& b);

    friend bool operator==(vectorInfo const& a, vectorInfo const& b);

};

Answer 1

//changed vector.cpp file , removed 'this' pointer usage where ever it is used , you can check my comments with keyword CHEGGEA , given output before modifying the code and also after modifying the code. Checked both output are same or not. There are same!!

//***vector.cpp file***

#include "vector.h"

vectorInfo::vectorInfo()

{

//this->x = 0;

//changed code to remove this ,CHEGGEA

x=0;

y=0;

//this->y = 0;

}

vectorInfo::vectorInfo(int x1, int y1)

{

//commented below code, CHEGGEA

//this->x = x;

//this->y = y;

//changed code to remove this ,CHEGGEA

x = x1;

y = y1;

}

void vectorInfo::set(int x1, int y1)

{

//this->x = x;

//this->y = y;

//changed code to remove this ,CHEGGEA

x = x1;

y = y1;

}

double vectorInfo::magnitude()

{

return sqrt(x * x + y * y);

}

double vectorInfo::direction()

{

return atan(y / x);

//can also use atan2(y, x) which is prefered, you can read about atan2 here : http://www.cplusplus.com/reference/cmath/atan2/

}

void vectorInfo::print()

{

cout << x << " " << y << endl;

}

vectorInfo vectorInfo::operator-(vectorInfo const& b)

{

//return vectorInfo(this->x - b.x, this->y - b.y);

//changed code to remove this ,CHEGGEA

return vectorInfo(x - b.x, y - b.y);

}

double vectorInfo::operator*(vectorInfo const& b)

{

//return this->x * b.x + this->y * b.y;

//changed code to remove this ,CHEGGEA

return x * b.x + y * b.y;

}

vectorInfo operator+(vectorInfo const& a, vectorInfo const& b)

{

return vectorInfo(a.x + b.x, a.y + b.y);

}

bool operator==(vectorInfo const& a, vectorInfo const& b)

{

return a.x == b.x && a.y == b.y;

}

/*Output before changing code

 ./main

v1 : 3 2

v2 : 5 4

v1 magnitude : 3.60555

v1 direction : 0.588003 radians

v1 + v2 : 8 6

v1 - v2 : -2 -2

v1 * v2 : 23

v1 == v2 : 0

//output after changing code

 ./main

v1 : 3 2

v2 : 5 4

v1 magnitude : 3.60555

v1 direction : 0.588003 radians

v1 + v2 : 8 6

v1 - v2 : -2 -2

v1 * v2 : 23

v1 == v2 : 0

*/