subtree(users/wpcarro): docking briefcase at '24f5a642' r/3226

git-subtree-dir: users/wpcarro
git-subtree-mainline: 464bbcb15c09813172c79820bcf526bb10cf4208
git-subtree-split: 24f5a642af3aa1627bbff977f0a101907a02c69f
Change-Id: I6105b3762b79126b3488359c95978cadb3efa789

1 files changed, 37 insertions, 0 deletions

diff --git a/users/wpcarro/scratch/data_structures_and_algorithms/recursive-string-permutations.py b/users/wpcarro/scratch/data_structures_and_algorithms/recursive-string-permutations.py
new file mode 100644
index 000000000000..70461ddf5dac
--- /dev/null
+++ b/users/wpcarro/scratch/data_structures_and_algorithms/recursive-string-permutations.py
@@ -0,0 +1,37 @@
+import unittest
+
+
+################################################################################
+# Implementation
+################################################################################
+# get_permutations :: String -> Set(String)
+def get_permutations(string):
+    pass
+
+
+################################################################################
+# Tests
+################################################################################
+class Test(unittest.TestCase):
+    def test_empty_string(self):
+        actual = get_permutations('')
+        expected = set([''])
+        self.assertEqual(actual, expected)
+
+    def test_one_character_string(self):
+        actual = get_permutations('a')
+        expected = set(['a'])
+        self.assertEqual(actual, expected)
+
+    def test_two_character_string(self):
+        actual = get_permutations('ab')
+        expected = set(['ab', 'ba'])
+        self.assertEqual(actual, expected)
+
+    def test_three_character_string(self):
+        actual = get_permutations('abc')
+        expected = set(['abc', 'acb', 'bac', 'bca', 'cab', 'cba'])
+        self.assertEqual(actual, expected)
+
+
+unittest.main(verbosity=2)