Thread: I need help with making a rectangle using a class!

Hey so I'm having trouble making this work. I do not know how to fix this code and I need some help!

Code:

#include "stdafx.h"
#include <iostream>
using namespace std;

class Rectangle {
    int width, height;
  public:
    void set_values (int,int);
    int area() {
       int answer;
      
       return answer;
    }
    Rectangle(int w, int h) {  // parameterized constructor
  
    }
};

void Rectangle::set_values (int x, int y) {
  
}

int main () {  

  Rectangle rect1(5,6);
  cout << "area: " << rect1.area() << endl;

  Rectangle rect2;
  rect2.set_values (3,4);
  cout << "area: " << rect2.area() << endl;
  return 0;
}

That looks to me like homework, where you've been given sample code to finish, but haven't done touched it yourself. Give a suggestion of how you think this could be solved and we can assist if problems arise.

it is homework, I believe that I have to change it so the class Rectangle can receive values and input it as its values.

I'm not a very avid coder, and I struggle a lot. I would really appreciate it if you can teach me how to do this!

Syntax for constructors is:

Code:

SomeClass(int a, int b)
{
    member_a = a;
    member_b = b;
}

// Modern approach via initialization list, preferred
SomeClass(int a, int b) : member_a(a), member_b(b)
{ }

What do you think the area() function needs to compute? It's a mathematical question, nothing about coding.

It needs to compute the area of the rectangle?

So, I had a lot of fun coding this up. It's so over-engineered that it can't possibly be turned in for a homework assignment: Compiler Explorer - C++

But that's some type-safe, awesome C++ for ya!

Boost's strong typedefs are severely underrated. The coolest part is, you can see in the assembly where the compiler calculates the area before the program is even run:

Code:

mov     esi, 169

It would appear that the entire class instance has been optimized down to a single integer.