#include<bits/stdc++.h>
using namespace std;
char a[1001], b[1001];
int f[1001][1001];        //  f[i][j]为使得a串的前i个字符包含b串的前j个字符的最小操作次数

int main()
{
    scanf("%s%s", a + 1, b + 1);
    int n = strlen(a + 1), m = strlen(b + 1);

    memset(f, 0x3f, sizeof f);
    f[0][0] = 0;

    for(int i = 1; i <= n; i ++)
    {
        f[i][0] = 0;
        for(int j = 1; j <= m; j ++)
        {
            f[i][j] = f[i - 1][j];
            if(a[i] == b[j])  f[i][j] = min(f[i][j], f[i - 1][j - 1]);
            else  f[i][j] = min(f[i][j], f[i - 1][j - 1] + 1);
        }
    }
    cout<<f[n][m];
    return 0;
}