1 files changed, 36 insertions, 0 deletions
diff --git a/challenge-219/roger-bell-west/python/ch-2.py b/challenge-219/roger-bell-west/python/ch-2.py
new file mode 100755
index 0000000000..d747e7ad69
--- /dev/null
+++ b/challenge-219/roger-bell-west/python/ch-2.py
@@ -0,0 +1,36 @@
+#! /usr/bin/python3
+
+from collections import deque
+
+def travelexpenditure(costs, days0):
+  days = sorted(days0)
+  validities = [1, 7, 30]
+  stack = deque()
+  stack.append([0, days])
+  cheapest = len(days) * costs[0]
+  while len(stack) > 0:
+    c = stack.popleft()
+    if len(c[1]) == 0:
+      if c[0] < cheapest:
+        cheapest = c[0]
+    else:
+      if c[0] >= cheapest:
+        continue
+      start = c[1][0]
+      for i in range(3):
+        end = start + validities[i] - 1
+        dtd = list(filter(lambda x: x > end, c[1]))
+        stack.append([c[0] + costs[i], dtd])
+  return cheapest
+
+import unittest
+
+class TestTravelexpenditure(unittest.TestCase):
+
+  def test_ex1(self):
+    self.assertEqual(travelexpenditure([2, 7, 25], [1, 5, 6, 7, 9, 15]), 11, 'example 1')
+
+  def test_ex2(self):
+    self.assertEqual(travelexpenditure([2, 7, 25], [1, 2, 3, 5, 7, 10, 11, 12, 14, 20, 30, 31]), 20, 'example 2')
+
+unittest.main()