#include<bits/stdc++.h>
using namespace std;
int main(){
	string s;
	cin>>s;
	char c1,c2;
	cin>>c1>>c2;
//	int p=s.find(c);
//	if(p==-1) cout<<s;
//	else{
//		while(p!=-1){
//			s.erase(p,1);
//			p=s.find(c,p);
//		}
//		cout<<s;
//	}
	for(int i=0;i<s.size();i++){
		if(s[i]==c1){
			cout<<c2;
		}else{
			cout<<s[i];
		}
	}
	return 0;
}

/**************************************************************
	Problem: 1570
	User: zhangziang
	Language: C++
	Result: Accepted
	Time:23 ms
	Memory:2076 kb
****************************************************************/