#include <bits/stdc++.h>
using namespace std;
int n, m;
string s;
string t;
const int MAXN = 1e3 + 7;
const int INF = 1e9;
int dp[MAXN][MAXN];
int lazy_dp(int pos_s, int pos_t){
    //cerr << pos_s << ' ' << pos_t << '\n';
    if (dp[pos_s][pos_t] < INF) return dp[pos_s][pos_t];
    if (pos_s > n || pos_t > m) return dp[pos_s][pos_t] = INF;
    if (pos_s == n && pos_t != m) return dp[pos_s][pos_t] = m - pos_t;
    if (pos_t == m && pos_s != n) return dp[pos_s][pos_t] = n - pos_s;
    if (pos_s == n && pos_t == m) return dp[pos_s][pos_t] = 0;
    if (s[pos_s] == t[pos_t]) return dp[pos_s][pos_t] = lazy_dp(pos_s + 1, pos_t + 1);
    cout << s[pos_s] << ' ' << t[pos_t] << ' ' << lazy_dp(pos_s + 1, pos_t) << ' ' << lazy_dp(pos_s, pos_t + 1) << ' ' << lazy_dp(pos_s + 1, pos_t + 1) << '\n';
    return dp[pos_s][pos_t] = (min(min(lazy_dp(pos_s + 1, pos_t), lazy_dp(pos_s, pos_t + 1)), lazy_dp(pos_s + 1, pos_t + 1)) + 1);
}
int main() {
    cin >> s;
    cin >> t;
    n = s.size();
    m = t.size();
    for (int i = 0;i < n;i++){
        for (int j = 0;j < m;j++) dp[i][j] = INF;
    }
    cout << lazy_dp(0, 0);
    return 0;
}