#include<iostream>
#include<unordered_set>

using namespace std;

string s1,s2;
int main()
{
    getline(cin,s1);
    getline(cin,s2);

    unordered_set<char> hash;
    for(auto c:s2) hash.insert(c);
    string res;
    for(auto c:s1)
        if(!hash.count(c))
            res+=c;
    cout<<res;
    return 0;
}