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

int main(){
	string str1;
	string str2;
	getline(cin,str1);
	getline(cin,str2);
	int len1 = str1.length();
	int len2 = str2.length();
	string str3 = "";
	bool flag = true;
	for(int i = 0; i<len1; i++){
		for(int j = 0; j <len2; j++){
			if(str1[i] == str2[j]){
				flag = false;
			}
		}
		if(flag){
			str3+=str1[i];
		}
		flag = true;
	}
	cout<<str3<<endl;
}