2018-10-31 13:08:44 +00:00
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#!/usr/bin/python3
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from itertools import count
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import random
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from util.io import readvalue
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def peter_coin_series(randf = random.randint):
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result = 0
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for k in count(1):
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if(randf(0, 1) < 0.5):
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return (result, k)
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2018-11-07 14:19:36 +00:00
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result = 2**k
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2018-10-31 13:08:44 +00:00
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if( __name__ == "__main__"):
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def positive_int(s):
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i = int(s)
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if(i <= 0):
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raise ValueError("{} is negative".format(i))
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return i
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print("I am going to toss a coin many times.\n"
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"You are going to win 2**k if no head appears afer k throws.\n")
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bet = readvalue("How many ducats do you want to bet? ", positive_int)
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result, throws = peter_coin_series()
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win = bet - result
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if(win < 0):
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print("Bad, A head came out on throw #{}. You lost {} ducats.".format(throws, -win))
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else:
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print("You won {} ducats.".format(win))
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