Assignment Statements

Im fairly new to C++ programming. My question is, Is it legal to put a double expression into an Int variable? If so what do I have to do?

Yes, though you'll probably get a warning telling you that it's not safe. You can silence the warning with a cast.

Code:

int i = static_cast<int>(123.456);

The net result is that everything past the radix will be truncated, and i will have the value 123. But, and there's usually a "but", if you have to use a cast, you're probably doing something you shouldn't be.

For example, if what you want is to remove any precision from a double value, you can do it with a library function, still use doubles, and avoid any casting.

Code:

#include <cmath>
#include <iostream>

using namespace std;

int main()
{
  double a = 123.456, b;

  cout<< modf(a, &b) <<endl;
  cout<< a <<'\n'<< b <<endl;
}

On top of that, modf also returns a normalized double for everything past the radix (0.456). Doing that with the casting method just feels icky.

Code:

#include <iostream>

using namespace std;

int main()
{
  double a = 123.456, b;
  int c;

  c = static_cast<int>(a);
  b = a - c;
  cout<< b <<endl;
  cout<< a <<'\n'<< c <<endl;
}

Thank you for showing the different way. This explains a lot.^^