mirror of https://github.com/python/cpython
34 lines
888 B
Python
Executable File
34 lines
888 B
Python
Executable File
#! /usr/bin/env python
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# Print digits of pi forever.
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#
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# The algorithm, using Python's 'long' integers ("bignums"), works
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# with continued fractions, and was conceived by Lambert Meertens.
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#
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# See also the ABC Programmer's Handbook, by Geurts, Meertens & Pemberton,
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# published by Prentice-Hall (UK) Ltd., 1990.
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import sys
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def main():
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k, a, b, a1, b1 = 2, 4, 1, 12, 4
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while True:
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# Next approximation
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p, q, k = k*k, 2*k+1, k+1
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a, b, a1, b1 = a1, b1, p*a+q*a1, p*b+q*b1
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# Print common digits
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d, d1 = a//b, a1//b1
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while d == d1:
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output(d)
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a, a1 = 10*(a%b), 10*(a1%b1)
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d, d1 = a//b, a1//b1
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def output(d):
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# Use write() to avoid spaces between the digits
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sys.stdout.write(str(d))
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# Flush so the output is seen immediately
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sys.stdout.flush()
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if __name__ == "__main__":
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main()
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