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C ++ Integer Function

I want to implement the largest integer function. [The largest integer function is the standard name for what is also known as the gender function.]

int x = 5/3;

My question with large numbers may be a loss of accuracy, since 5/3 will lead to double?

EDIT: The largest integer function is an integer less than or equal to X. Example:

4.5 = 4
4 = 4
3.2 = 3
3 = 3

What I want to know is 5/3 to create a double? Because if that is the case, I will have a loss of precision when converting to int.

Hope this makes sense.

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5 answers

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:

#include <cmath>

inline long
floordiv (long num, long den)
{
  if (0 < (num^den))
    return num/den;
  else
    {
      ldiv_t res = ldiv(num,den);
      return (res.rem)? res.quot-1 
                      : res.quot;
    }
}

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