Initial data commit

Task/Semordnilap/Python/semordnilap-3.py

@@ -0,0 +1,50 @@
+import sys
+import random
+import requests
+
+URL = 'http://wiki.puzzlers.org/pub/wordlists/unixdict.txt'
+
+
+def find_semordnilaps(word_generator):
+
+  # Keys in this dict are the words seen so far, reversed.
+  # Values are booleans determining whether we have seen (and yielded)
+  # the key, so that we don't yield the same word twice.
+  seen = {}
+
+  for word in word_generator:
+    if word not in seen:
+      reversed_word = word[::-1]
+      seen[reversed_word] = False  # not yielded yet
+    else:
+      yielded_already = seen[word]
+      if not yielded_already:
+        yield word
+        seen[word] = True  # the word has been yielded
+
+
+def url_lines(url):
+  with requests.get(url, stream=True) as req:
+    yield from req.iter_lines(decode_unicode=True)
+
+
+def main(url=URL, num_of_examples=5):
+
+  semordnilaps_generator = find_semordnilaps(url_lines(url))
+
+  semordnilaps = list(semordnilaps_generator)
+
+  example_words = random.choices(semordnilaps, k=int(num_of_examples))
+  example_pairs = ((word, word[::-1]) for word in example_words)
+
+  print(
+    f'found {len(semordnilaps)} semordnilap words:',
+    * ['%s %s' % p for p in example_pairs]+['...'],
+    sep='\n'
+  )
+
+  return semordnilaps
+
+
+if __name__ == '__main__':
+  main(*sys.argv[1:])