[LeetCode]72.Edit Distance

题目

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

思路

具体参考：[经典面试题]字符串编辑距离

思路一 超时

代码

    /*--------------------------------------------
    *   日期：2014-03-01
    *   作者：SJF0115
    *   题目: 72.Edit Distance
    *   网址：https://oj.leetcode.com/problems/edit-distance/
    *   结果：AC
    *   来源：LeetCode
    *   博客：
    ------------------------------------------------*/
    #include <iostream>
    #include <vector>
    using namespace std;

        class Solution {
    public:
        int minDistance(string word1, string word2) {
            int m = word1.size();
            int n = word2.size();
            // Edit[i][j]为word1[0..i-1]和word2[0..j-1]的最小编辑数
            int Edit[m+1][n+1];
            // 初始化
            for(int i = 0;i <= m;++i){
                Edit[i][0] = i;
            }//for
            for(int i = 0;i <= n;++i){
                Edit[0][i] = i;
            }//for
            for(int i = 1;i <= m;++i){
                for(int j = 1;j <= n;++j){
                    // 当前字符相同
                    if(word1[i-1] == word2[j-1]){
                        Edit[i][j] = Edit[i-1][j-1];
                    }//if
                    else{
                        Edit[i][j] = 1 + min(Edit[i-1][j-1],min(Edit[i-1][j],Edit[i][j-1]));
                    }//else
                }//for
            }//for
            return Edit[m][n];
        }
    };

    int main(){
        Solution solution;
        string str1("ab");
        string str2("bc");
        cout<<solution.minDistance(str1,str2)<<endl;
        return 0;
    }

运行时间

<script type="text/javascript"> $(function () { $('pre.prettyprint code').each(function () { var lines = $(this).text().split('\n').length; var $numbering = $('<ul/>').addClass('pre-numbering').hide(); $(this).addClass('has-numbering').parent().append($numbering); for (i = 1; i <= lines; i++) { $numbering.append($('<li/>').text(i)); }; $numbering.fadeIn(1700); }); }); </script>