38 lines
744 B
Python
38 lines
744 B
Python
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def is_increasing(n_str):
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if len(n_str) < 2:
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return True
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if n_str[0] <= n_str[1]:
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return is_increasing(n_str[1:])
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return False
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def is_decreasing(n_str):
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if len(n_str) < 2:
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return True
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if n_str[0] >= n_str[1]:
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return is_decreasing(n_str[1:])
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return False
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def is_bouncy(n_str):
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return not (is_increasing(n_str) or is_decreasing(n_str))
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def euler_112():
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n, n_bouncy = 0, 0
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while True:
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n += 1
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if is_bouncy(str(n)):
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n_bouncy += 1
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ratio = n_bouncy / n
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if ratio >= 0.99:
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return n
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if __name__ == "__main__":
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solution = euler_112()
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print("e112.py: " + str(solution))
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assert(solution == 1587000)
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