#include<iostream>
#include<algorithm>
#include<string.h>
using namespace std;

char s1[1010];
char s2[1010];

int len1;
int len2;

int DP[1010][1010];

int main(){
    scanf("%s", &s1[1]);
    scanf("%s", &s2[1]);

    len1 = strlen(&s1[1]);
    len2 = strlen(&s2[1]);

    //----------------Solution-------------

    for(int i= 1; i <=len1; i++){
        for(int j =1; j<= len2; j++){
            if(s1[i] == s2[j])
                DP[i][j] = DP[i-1][j-1]+1;
            else
                DP[i][j] = max(DP[i-1][j], DP[i][j-1]);
        }
    }
    

    printf("%d", DP[len1][len2]);
    
    return 0;
}