tasks a-s

Task/Palindrome-detection/Python/palindrome-detection-1.py

@@ -0,0 +1,2 @@
+def is_palindrome(s):
+  return s == s[::-1]

Task/Palindrome-detection/Python/palindrome-detection-2.py

@@ -0,0 +1,7 @@
+def is_palindrome_r(s):
+  if len(s) <= 1:
+    return True
+  elif s[0] != s[-1]:
+    return False
+  else:
+    return is_palindrome_r(s[1:-1])

Task/Palindrome-detection/Python/palindrome-detection-3.py

@@ -0,0 +1,2 @@
+def is_palindrome_r2(s):
+  return not s or s[0] == s[-1] and is_palindrome_r2(s[1:-1])

Task/Palindrome-detection/Python/palindrome-detection-4.py

@@ -0,0 +1,9 @@
+def test(f, good, bad):
+  assert all(f(x) for x in good)
+  assert not any(f(x) for x in bad)
+  print '%s passed all %d tests' % (f.__name__, len(good)+len(bad))
+
+pals = ('', 'a', 'aa', 'aba', 'abba')
+notpals = ('aA', 'abA', 'abxBa', 'abxxBa')
+for ispal in is_palindrome, is_palindrome_r, is_palindrome_r2:
+  test(ispal, pals, notpals)