Project Euler -- Problem 19

euler19.fs

let euler19 () =
    let mutable k = 0
    for y in 1901 .. 2000 do
        for m in 1 .. 12 do
            let date = System.DateTime(y, m, 1)
            if date.DayOfWeek = System.DayOfWeek.Sunday then
                k <- k + 1
    k

stdout.WriteLine(euler19 ())

euler19.py

from calendar import Calendar

counter = 0
iterator = Calendar()

for y in xrange(1901,2001):
    for m in xrange(1,13):
        for d in iterator.itermonthdays2(y,m):
            if d == (1,6):
                counter += 1

print counter