本文实例讲述了Python基于动态规划算法计算单词距离。分享给大家供大家参考。具体如下:
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#!/usr/bin/env python #coding=utf-8 def word_distance(m,n): """compute the least steps number to convert m to n by insert , delete , replace . 动态规划算法,计算单词距离 >>> print word_distance("abc","abec") 1 >>> print word_distance("ababec","abc") 3 """ len_1 = lambda x: len (x) + 1 c = [[i] for i in range ( 0 ,len_1(m)) ] c[ 0 ] = [j for j in range ( 0 ,len_1(n))] for i in range ( 0 , len (m)): # print i,' ', for j in range ( 0 , len (n)): c[i + 1 ].append( min ( c[i][j + 1 ] + 1 , #插入n[j] c[i + 1 ][j] + 1 , #删除m[j] c[i][j] + ( 0 if m[i] = = n[j] else 1 ) #改 ) ) # print c[i+1][j+1],m[i],n[j],' ', # print '' return c[ - 1 ][ - 1 ] import doctest doctest.testmod() raw_input ( "Success!" ) |
希望本文所述对大家的Python程序设计有所帮助。