Question Overload the and operators for the square class w

Question:

Overload the + and = operators for the square class we have provided you.

The = should make a deep copy of the square object.

The + operator should concatenate the names of the two squares and add their lengths.

Explain why we should be overloading the assignment operator in a comment.

given code:

//main.cpp

#include <iostream>

#include <string>

using namespace std;

int main(){

Square a;

Square b = a;

Square c(a);

return 0;

}

//square.cpp

#include <iostream>

#include <string>

using namespace std;

#include \"square.h\"

Square::Square() {

name = \"mysquare\";

lengthptr = new double;

*lengthptr = 2.0;

}

void Square::setName(string newName) {

name = newName;

}

void Square::setLength(double newVal) {

*lengthptr = newVal;

}

string Square::getName() const {

return name;

}

double Square::getLength() const {

return *lengthptr;

}

Square::Square(const Square & other) {

cout << \"I am copying!\" << endl;

name = other.getName();

lengthptr = new double;

*lengthptr = other.getLength();

}

Square::~Square() {

delete lengthptr;

}

//square.h

#ifndef _SQUARE_H

#define _SQUARE_H

class Square {

private:

string name;

double * lengthptr;

public:

Square();

Square(const Square & old);

~Square();

void setName(string newName);

void setLength(double newVal);

string getName() const;

double getLength() const;

};

#endif

//Makefile

EXENAME = main

CXX = clang++
CXXFLAGS = -std=c++0x -g -O0 -Wall -Wextra

all : $(EXENAME)

$(EXENAME): main.cpp square.cpp square.h
   $(CXX) $(CXXFLAGS) main.cpp square.cpp -o $(EXENAME)

.PHONY: clean
clean:
   rm -f $(EXENAME)

Solution

//Put this code in square.cpp file
//Overloading + operator

Square Square::operator+(const Square& square)
{
//Creating a new square object for representing the result
Square result = new Square();
  
string newName;
//Concatenating both names and storing the result in \"result\" object\'s name
strcat(newName, name);
strcat(newName, square.getName());
result.setName(newName);
  
//Adding both lengths and storing in result object
double newLength = 0;
newLength = square.getLength() + *lengthptr;
result.setLength(newLength);
  
return result;
}

//Overloading the = operator
//Reason why we have to overload the assignment operator
//The default assignment operator performs a bit pattern copy i.e.
//simply copies data members of one object into another object.
//It works fine, until class member isn\'t allocated any resource(file or memory)
//Hence it performs a shallow copy by default (i.e copying data members irrespective of their type)
//To perform deep copy(i.e pointers must not be copied,
//instead there should be separate memory allocation for them)
//we need to overload the assignment operator and create a custom copy constructor for the class

void Square::operator=(const Square& square)
{
name = square.getName();
*lengthptr = square.getLength();
}