30 lines
624 B
Python
30 lines
624 B
Python
from math import factorial
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from itertools import combinations
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def product(xs):
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r = 1
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for x in xs:
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r *= x
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return r
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def sub_odds(n_blue, n_total):
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odds = [n for n in range(1, n_total + 1)]
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return sum(map(product, combinations(odds, n_total - n_blue)))
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def euler_121():
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n_turns = 15
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n_to_win = n_turns // 2 + 1
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odds = sum([sub_odds(n_blue, n_turns)
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for n_blue in range(n_to_win, n_turns + 1)])
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return int(factorial(n_turns + 1) / odds)
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if __name__ == "__main__":
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solution = euler_121()
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print("e121.py: " + str(solution))
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assert(solution == 2269)
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