Question

Keep getting this error message when trying to compile in main1.cpp. Need help figuring out how to make it compile. Thank you for your time.

Error Message:

main.cpp:(.text+0x13): undefined reference to `circle::circle()'

main.cpp:(.text+0x32): undefined reference to `circle::circle(double)'

main.cpp:(.text+0x3e): undefined reference to `circle::getArea() const'

main.cpp:(.text+0x53): undefined reference to `circle::getRadius() const'

main.cpp:(.text+0xb3): undefined reference to `circle::getArea() const'

main.cpp:(.text+0xc8): undefined reference to `circle::getRadius() const'

main.cpp:(.text+0x157): undefined reference to `circle::setRadius(double)'

main.cpp:(.text+0x163): undefined reference to `circle::getArea() const'

main.cpp:(.text+0x178): undefined reference to `circle::getRadius() const'

main.cpp:(.text+0x207): undefined reference to `circle::setRadius(double)'

main.cpp:(.text+0x213): undefined reference to `circle::getArea() const'

main.cpp:(.text+0x228): undefined reference to `circle::getRadius() const'

collect2: error: ld returned 1 exit status

Main1.cpp

#include <iostream>

using namespace std;

#include "circle.h"

int main()

{

circle circle1, circle2;

int radius;

cout<< "Enter Radius for circle 1: ";

cin >> radius;

circle1.setRadius(radius);

cout << "Enter Radius for circle 2: ";

cin>> radius;

circle2.setRadius(radius);

cout<< endl;

cout<< "Radius of Circle 1: " << circle1.getRadius() << endl;

cout<< "Area of Circle 1: " << circle1.calcArea()<< endl;

cout << "Radius of Circle 2: " << circle2.getRadius() << endl;

cout << "Area of Circle 2: " << circle2.calcArea() << endl;

return 0;

}

circle.cpp

#include <iostream>

#include "circle.h"

using namespace std;

const double PI = 3.14159;

circle::circle()

{

radius = 0;

}

circle::circle(int r)

{

if(r < 0)

{

r = 0;

}

radius = r;

}

void circle::setRadius(int r)

{

radius = r;

}

int circle::getRadius()

{

return radius;

}

double circle::calcArea()

{

return PI*radius*radius;

}

circle.h

#ifndef CIRCLE_H

#define CIRCLE_H

class circle

{

private:

int radius;

public:

circle();

circle(int r);

void setRadius(int r);

int getRadius();

double calcArea();

};

#endif

Answer 1

It compiles fine..did you copy whole text along with circle.h like this ?

circle.h

#ifndef CIRCLE_H

#define CIRCLE_H

class circle

{

private:

int radius;

public:

circle();

circle(int r);

void setRadius(int r);

int getRadius();

double calcArea();

};

#endif

Then comment out the first line circle.h like this //circle.h

similarly if you have copied whole text for circle.cpp ,, then comment out circle.cpp at the beginning . Then it should be fine.

//I executed your program and got output as below

Enter Radius for circle 1: 2
Enter Radius for circle 2: 4

Radius of Circle 1: 2
Area of Circle 1: 12.5664
Radius of Circle 2: 4
Area of Circle 2: 50.2654