tvl-depot/data_structures_and_algorithms/which-appears-twice.py
William Carroll 5c9079a410 Splice ./universe directory into ./
Manually merging:
- README.md: I added the description from universe/README.md into the heading of
  dotfiles/README.md.
- .envrc: dotfiles/.envrc was a superset of universe/.envrc
- .gitignore: Adding some of the ignored patterns from universe/.gitignore to
  dotfiles/.gitignore

Everything else here should be a simple rename.
2020-01-29 14:43:20 +00:00

33 lines
966 B
Python

import unittest
################################################################################
# Solution
################################################################################
# find_repeat :: [Int] -> Int
def find_repeat(xs):
n = len(xs) - 1
return sum(xs) - ((n**2 + n) / 2)
################################################################################
# Tests
################################################################################
class Test(unittest.TestCase):
def test_short_list(self):
actual = find_repeat([1, 2, 1])
expected = 1
self.assertEqual(actual, expected)
def test_medium_list(self):
actual = find_repeat([4, 1, 3, 4, 2])
expected = 4
self.assertEqual(actual, expected)
def test_long_list(self):
actual = find_repeat([1, 5, 9, 7, 2, 6, 3, 8, 2, 4])
expected = 2
self.assertEqual(actual, expected)
unittest.main(verbosity=2)