1 files changed, 36 insertions, 0 deletions
diff --git a/challenge-126/roger-bell-west/python/ch-1.py b/challenge-126/roger-bell-west/python/ch-1.py
new file mode 100755
index 0000000000..d50faf6626
--- /dev/null
+++ b/challenge-126/roger-bell-west/python/ch-1.py
@@ -0,0 +1,36 @@
+#! /usr/bin/python3
+
+import unittest
+
+def cn(n):
+  k=n
+  digits=[]
+  while k>0:
+    d=k % 10
+    if d==1:
+      digits=[8] * len(digits)
+    if d>0:
+      d -= 1
+    digits.append(d)
+    k=int(k/10)
+  tc=0
+  for i in range(len(digits)-1,-1,-1):
+    tc *= 9
+    tc += digits[i]
+  return tc
+
+class TestCn(unittest.TestCase):
+
+        def test_ex1(self):
+          self.assertEqual(cn(15),8,'example 1')
+
+        def test_ex2(self):
+          self.assertEqual(cn(25),13,'example 2')
+
+        def test_ex3(self):
+          self.assertEqual(cn(10000),6560,'example 3')
+
+        def test_ex4(self):
+          self.assertEqual(cn(100000000),43046720,'example 3')
+          
+unittest.main()