I Have I(rritable)B(owel)S(yndrome)

So I didn't ammend. Anyway, the name of this template is "Colorful Shirt", not "Plaid". It sounded wrong when I was typing it in, but who am I to argue with the crazy complexities of the universe. Speaking of the universe's crazy complexities, can anyone (excluding Carlos and Michelle) tell me what the following algorithm is used for?

    c = y / 100
    n = y - 19 * ( y / 19 )
    k = ( c - 17 ) / 25
    i = c - c / 4 - ( c - k ) / 3 + 19 * n + 15
    i = i - 30 * ( i / 30 )
    i = i - ( i / 28 ) * ( 1 - ( i / 28 ) * ( 29 / ( i + 1 ) )
        * ( ( 21 - n ) / 11 ) )
    j = y + y / 4 + i + 2 - c + c / 4
    j = j - 7 * ( j / 7 )
    l = i - j
    m = 3 + ( l + 40 ) / 44
    d = l + 28 - 31 * ( m / 4 )

Good luck. The winner gets to know something important. And yes, it is simply the knowledge of the algorithm. I am still quite cheap.