#include<iostream>
#include<vector>
using namespace std;
int main()
{
    string word1,word2;
    while(cin>>word1>>word2)
    {
        int m=word1.size();
        int n=word2.size();
        vector<vector<int>>dp(m+1,vector<int>(n+1,0));
        for(int i=0;i<m+1;i++)dp[i][0]=i;
        for(int j=0;j<n+1;j++)dp[0][j]=j;
        for(int i=1;i<m+1;i++)
        {
            for(int j=1;j<n+1;j++)
            {
                int v=0;
                if(word1[i-1]!=word2[j-1])
                {
                    v=1;
                }
               dp[i][j]=min(min(dp[i-1][j]+1,dp[i][j-1]+1),dp[i-1][j-1]+v);
            }
        }
       cout<<dp[m][n]<<endl;
    }
    return 0;
}