32 lines
623 B
Python
32 lines
623 B
Python
#coding: utf-8
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''' mbinary
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#######################################################################
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# File : fastPow.py
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# Author: mbinary
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# Mail: zhuheqin1@gmail.com
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# Blog: https://mbinary.xyz
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# Github: https://github.com/mbinary
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# Created Time: 2018-12-17 21:39
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# Description: fast power
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#######################################################################
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'''
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def fastPow(a,n):
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'''a^n'''
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rst = 1
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while n:
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if n%2:
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rst *=a
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n>>=1
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a*=a
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return rst
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def fastMul(a,b):
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'''a*b'''
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rst = 0
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while b:
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if b&1:
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rst +=a
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b>>=1
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a*=2
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