"""Counting Sundays

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)?
"""

@@ -544,8 +544,495 @@
 0)?%0A%22%22%22%0A
+import calendar%0A%0A%0AMONTHS = 12%0ASUNDAY = 6%0A%0A%0Adef get_first_sundays(low_year, high_year):%0A    %22%22%22%0A    Find the number of Sundays falling on the first of the month between low_year%0A    and high_year, inclusive.%0A    %22%22%22%0A    first_sundays = 0%0A%0A    for year in range(low_year, high_year + 1):%0A        for month in range(1, MONTHS + 1):%0A            first_day, _ = calendar.monthrange(year, month)%0A%0A            if first_day == SUNDAY:%0A                first_sundays += 1%0A%0A    return first_sundays%0A

Add solution for problem 19