28 lines
615 B
Python
28 lines
615 B
Python
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#!/usr/bin/python
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from random import choice, seed
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def ht():
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"""Toss a coin and return H or T."""
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return choice(["H", "T"])
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def numberoftosses(pattern):
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"""Return the number of tosses until we hit the pattern."""
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s = len(pattern) * ht()
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while s[-len(pattern):] != pattern:
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s += ht()
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return(len(s))
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def avgnumberoftosses(pattern, tries = 10000):
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"""Return the average number of tosses until we hit the pattern."""
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n = 0.0
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for t in range(tries):
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n += numberoftosses(pattern)
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n /= tries
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return n
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seed()
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for pattern in "HTH", "HTT":
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print pattern, round(avgnumberoftosses(pattern))
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