LeetCode-Edit Distance

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

class Solution {
public:
    int minDistance(string word1, string word2) {
        // Note: The Solution object is instantiated only once and is reused by each test case.
        vector<vector<int> > p;
        vector<int> one;
        one.resize(word2.length()+1);
        p.resize(word1.length()+1,one);
        int m=word1.length();
        int n=word2.length();
        for(int i=0;i<=m;i++)p[i][0]=i;
        for(int i=0;i<=n;i++)p[0][i]=i;
        for(int i=1;i<=m;i++){
            for(int j=1;j<=n;j++){
                p[i][j]=min(min(p[i-1][j]+1,p[i][j-1]+1),(p[i-1][j-1]+(word1[i-1]==word2[j-1]?0:1)));
            }
        }
        return p[m][n];
    }
};