1 files changed, 39 insertions, 0 deletions
diff --git a/challenge-193/sgreen/python/ch-2.py b/challenge-193/sgreen/python/ch-2.py
new file mode 100755
index 0000000000..cdc2d772f6
--- /dev/null
+++ b/challenge-193/sgreen/python/ch-2.py
@@ -0,0 +1,39 @@
+#!/usr/bin/env python3
+
+import string
+import sys
+
+
+def main(s):
+    # Create letter to number mapping
+    letter_map = {}
+    for k, v in enumerate(string.ascii_lowercase):
+        letter_map[v] = k
+
+    occurrences = {}
+    for word in s:
+        # Calculate the differences between characters, and store this
+        #  as a space separated string
+        diff = ' '.join([
+            str(letter_map[word[i]] - letter_map[word[i-1]])
+            for i in range(1, len(word))
+        ])
+
+        # Add the word to the occurrences dict
+        if diff not in occurrences:
+            occurrences[diff] = []
+        occurrences[diff].append(word)
+
+    # Find the unique words
+    unique_words = [v[0] for v in occurrences.values() if len(v) == 1]
+
+    if len(unique_words) > 1:
+        print('More than one unique string!')
+    elif len(unique_words) == 0:
+        print('No unique strings!')
+    else:
+        print(unique_words[0])
+
+
+if __name__ == '__main__':
+    main(sys.argv[1:])