kasajian/day-of-week.md

## day-of-week.md

      
    Raw
  

              day-of-week.md
            
          
    Code:
/* 0 = Sunday, 1 <= m <= 12, y > 1752 or so */
int dayofweek(int y, int m, int d)
{
    static int t[] = {0, 3, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4};
    y -= m < 3;
    return (y + y/4 - y/100 + y/400 + t[m-1] + d) % 7;
}
More:
http://en.wikipedia.org/wiki/Determination_of_the_day_of_the_week