Add solution to Martin Luther King Day exercise

Currently this solution is not automatically tested, but was
manually tested using Python 3.6.5.

2 files changed, 51 insertions, 0 deletions

diff --git a/docs/exercises/index.rst b/docs/exercises/index.rst
index 85c7e0b..e5e5783 100644
--- a/docs/exercises/index.rst
+++ b/docs/exercises/index.rst
@@ -11,6 +11,8 @@ If you are interested in helping improve the documentation of ``dateutil``, it i
     :local:
 
 
+.. _mlk-day-exercise:
+
 Martin Luther King Day
 --------------------------------
 
@@ -66,6 +68,7 @@ To solve this exercise, copy-paste this script into a document, change anything
 
     </details>
 
+A solution to this problem is provided :doc:`here <solutions/mlk-day-rrule>`.
 
 
 Next Monday meeting
diff --git a/docs/exercises/solutions/mlk-day-rrule.rst b/docs/exercises/solutions/mlk-day-rrule.rst
new file mode 100644
index 0000000..b8da806
--- /dev/null
+++ b/docs/exercises/solutions/mlk-day-rrule.rst
@@ -0,0 +1,48 @@
+:orphan:
+
+Martin Luther King Day: Solution
+================================
+
+Presented here is a solution to the :ref:`Martin Luther King Day exercises <mlk-day-exercise>`.
+
+
+.. code-block:: python3
+
+    # ------- YOUR CODE -------------#
+    from dateutil import rrule
+    from datetime import datetime
+
+    MLK_DAY = rrule.rrule(
+        dtstart=datetime(1986, 1, 20),      # First celebration
+        freq=rrule.YEARLY,                  # Occurs once per year
+        bymonth=1,                          # In January
+        byweekday=rrule.MO(+3),             # On the 3rd Monday
+    )
+
+    # -------------------------------#
+
+    from datetime import datetime
+    MLK_TEST_CASES = [
+        ((datetime(1970, 1, 1), datetime(1980, 1, 1)),
+         []),
+        ((datetime(1980, 1, 1), datetime(1989, 1, 1)),
+         [datetime(1986, 1, 20),
+          datetime(1987, 1, 19),
+          datetime(1988, 1, 18)]),
+        ((datetime(2017, 2, 1), datetime(2022, 2, 1)),
+         [datetime(2018, 1, 15, 0, 0),
+          datetime(2019, 1, 21, 0, 0),
+          datetime(2020, 1, 20, 0, 0),
+          datetime(2021, 1, 18, 0, 0),
+          datetime(2022, 1, 17, 0, 0)]
+         ),
+    ]
+
+    def test_mlk_day():
+        for (between_args, expected) in MLK_TEST_CASES:
+            assert MLK_DAY.between(*between_args) == expected
+
+    if __name__ == "__main__":
+        test_mlk_day()
+        print('Success!')
+