Seongbeom Park
6269b9b896
Verifying solution... Test 1 passed! Test 2 passed! Test 3 failed [Hidden] Test 4 passed! [Hidden] Test 5 failed [Hidden]
51 lines
1.5 KiB
Python
51 lines
1.5 KiB
Python
def solution(banana_list):
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fewest_possible_number = len(banana_list)
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memo = {}
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for pairs in generate_trainer_pairs(list(range(len(banana_list)))):
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possible_number = len(banana_list)
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for i, j in pairs:
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if check_loop(banana_list[i], banana_list[j], memo):
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possible_number -= 2
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if possible_number < fewest_possible_number:
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fewest_possible_number = possible_number
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if fewest_possible_number < 2: # early termination
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break
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return fewest_possible_number
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import copy
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def generate_trainer_pairs(trainer_id_list):
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if len(trainer_id_list) < 2:
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yield []
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else:
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first_id = trainer_id_list[0]
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for second_id in trainer_id_list[1:]:
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reduced_list = copy.deepcopy(trainer_id_list)
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seduced_list.remove(first_id)
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reduced_list.remove(second_id)
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for pairs in generate_trainer_pairs(reduced_list):
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yield [(first_id, second_id)] + pairs
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def check_loop(a, b, memo):
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if (a, b) in memo:
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return memo[(a, b)]
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while a != b:
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if (a + b) % 2 == 1: # sum is odd
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memo[(a, b)] = True
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return True
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if a > b:
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a, b = (a - b)/2, b
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else:
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a, b = a, (b - a)/2
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memo[(a, b)] = False
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return False
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tests = [
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([1], 1),
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([1, 1], 2),
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([1, 7, 3, 21, 13, 19], 0),
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]
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for i, o in tests:
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result = solution(i)
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print(i, result == o, result, o)
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