splitting.py

a = 'a'
b = 'b'
c = 'c'
d = 'd'

def test_empty():
    check([], 0)

def test_all_one():
    check([a, a], 1)
    check([a, a, a, a], 1)

def test_two_types():
    check([a, b], 1)
    check([a, b, a, b], 2)

def test_harder():
    check([a, a, b, b, c, d], 3)

def check(cookies, expected_num_unique_left):
    assert len(cookies) % 2 == 0
    assert num_unique_left(cookies) == expected_num_unique_left