[Gammix]

Here is the magic code: (it take cares of leap years as well)

pawn Код:

rdn(year, month, day) // Rata Die day
{
    if (month < 3)
    {
        year--;
        month += 12;
    }
    return ((365*year) + (year/4) - (year/100) + (year/400) + (((153*month) - 457)/5) + (day - 306));
}

How to use:

pawn Код:

new num_days = (rdn(2017, 1, 1) - rdn(2016, 1, 1));