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59 lines
1.3 KiB
Python
59 lines
1.3 KiB
Python
#coding: utf-8
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''' mbinary
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#########################################################################
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# File : KMP.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: 2018-12-11 14:02
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# Description:
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#########################################################################
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'''
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def getPrefixFunc(s):
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'''return the list of prefix function of s'''
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length = 0
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i = 1
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n = len(s)
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ret = [0]
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while i<n:
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if s[i]==s[length]:
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length +=1
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ret.append(length)
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i+=1
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else:
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if length==0:
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ret.append(0)
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i+=1
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else:
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length = ret[length-1]
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return ret
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def findAll(s,p):
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pre = getPrefixFunc(p)
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i = j =0
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n,m = len(s),len(p)
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ret = []
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while i<n:
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if s[i]==p[j]:
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i+=1
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j+=1
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if j==m:
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ret.append(i-j)
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j=pre[j-1]
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else:
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if j==0: i+=1
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else: j = pre[j-1]
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return ret
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def randStr(n=3):
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return [randint(ord('a'),ord('z')) for i in range(n)]
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if __name__ =='__main__':
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from random import randint
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s = randStr(50)
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p = randStr(1)
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print(s)
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print(p)
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print(findAll(s,p))
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