#include <fstream>
#include <cmath>
#include <vector>
#include <algorithm>
#include <map>
#include <string>
#include <bitset>
#define pb(a) push_back(a)
using namespace std;

ifstream cin("subsir.in");
ofstream cout("subsir.out");

int dp[501][501];
string a, b;

int main(){
    cin >> a >> b;
    for(int i = 0; i < a.size(); ++i){
        for(int j = 0; j < b.size(); ++j){
            if(a[i] == b[j]){
                dp[i][j] = dp[i - 1][j - 1] + 1;
            }
            else{
                dp[i][j] = max(dp[i - 1][j], dp[i][j - 1]);
            }
        }
    }
    cout << dp[a.size() - 1][b.size() - 1];
    return 0;
}