minimum_edit_distance.cpp

class Solution {
public:
    int minDistance(string word1, string word2) {
        
        int M = word1.size(), N = word2.size();
        
        vector<vector<int>> dp(M + 1, vector<int> (N + 1, 0));
        
        for(int i=1; i<=M; i++)
            dp[i][0] = i;
        
        for(int j=1; j<=N; j++)
            dp[0][j] = j;
        
        
        for(int i=1; i<=M; i++){
            for(int j=1; j<=N; j++){

                if(word1[i-1] == word2[j-1])
                    dp[i][j] = dp[i-1][j-1];
                else{
                    dp[i][j] = min(dp[i-1][j], min(dp[i][j-1], dp[i-1][j-1])) + 1;
                }
                
            }
        }
        return dp[M][N];
    }
};