标签：style blog io ar color sp for on div
Given two words word1 and word2, find the minimum number of steps required to convert word1 to word2. (each operation is counted as 1 step.)
You have the following 3 operations permitted on a word:
a) Insert a character
b) Delete a character
c) Replace a character
分析：用动态规划来解，f[i][j]表示word1[0,i-1]与word2[0,j-1]的edit distance。当word1[i] == word2[j]时，f[i][j] = f[i-1][j-1]；否则，f[i][j]为f[i-1][j]+1（delete a character）、f[i][j-1]+1（insert a character）、f[i-1][j-1]+1（replace a character）中的最小值。
1 class Solution { 2 public: 3 int minDistance(string word1, string word2) { 4 int m = word1.length(), n = word2.length(); 5 if(m == 0 || n == 0) return abs(m-n); 6 int record[m+1][n+1]; 7 for(int i = 0; i <= m; i++) 8 record[i][0] = i; 9 for(int j = 0; j <= n; j++) 10 record[0][j] = j; 11 for(int i = 1; i <= m; i++) 12 for(int j = 1; j <= n; j++){ 13 if(word1[i-1] == word2[j-1]) record[i][j] = record[i-1][j-1]; 14 else{ 15 int min_step = min(record[i-1][j],record[i][j-1]); 16 record[i][j] = min(min_step,record[i-1][j-1]) + 1; 17 } 18 } 19 return record[m][n]; 20 } 21 };
标签：style blog io ar color sp for on div
原文地址：http://www.cnblogs.com/Kai-Xing/p/3926854.html
