1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
|
import unittest
from math import floor
################################################################################
# Solution
################################################################################
# change_possibilities :: Int -> [Int] -> Int
def change_possibilities(n, xs):
combinations = [0] * (n + 1)
combinations[0] = 1
for x in xs:
for i in range(len(combinations)):
if i >= x:
combinations[i] += combinations[i - x]
return combinations[n]
################################################################################
# Tests
################################################################################
class Test(unittest.TestCase):
def test_sample_input(self):
actual = change_possibilities(4, (1, 2, 3))
expected = 4
self.assertEqual(actual, expected)
def test_one_way_to_make_zero_cents(self):
actual = change_possibilities(0, (1, 2))
expected = 1
self.assertEqual(actual, expected)
def test_no_ways_if_no_coins(self):
actual = change_possibilities(1, ())
expected = 0
self.assertEqual(actual, expected)
def test_big_coin_value(self):
actual = change_possibilities(5, (25, 50))
expected = 0
self.assertEqual(actual, expected)
def test_big_target_amount(self):
actual = change_possibilities(50, (5, 10))
expected = 6
self.assertEqual(actual, expected)
def test_change_for_one_dollar(self):
actual = change_possibilities(100, (1, 5, 10, 25, 50))
expected = 292
self.assertEqual(actual, expected)
unittest.main(verbosity=2)
|
