# You are given the following information, but you may prefer to do some research for yourself.

# 1 Jan 1900 was a Monday.
# Thirty days has September,
# April, June and November.
# All the rest have thirty-one,
# Saving February alone,
# Which has twenty-eight, rain or shine.
# And on leap years, twenty-nine.
# A leap year occurs on any year evenly divisible by 4, but not on a century unless it is divisible by 400.
# How many Sundays fell on the first of the month during the twentieth century (1 Jan 1901 to 31 Dec 2000)?
import datetime #just for checking 

def howManySundays():
  sundays = 0
  for year in range(1901,2001):
    for month in range(1,13):
      candidate = datetime.date(year,month,1)
      if candidate.weekday() == 6:
        sundays += 1
  return sundays      


print howManySundays()