#include <fstream>
using namespace std;
ifstream cin("subsir.in");
ofstream cout("subsir.out");
string a, b;
int dp[512][512];

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