// editor3
import java.util.*;
public class Main{
    public static void main(String args[]){
        Scanner sc=new Scanner(System.in);
        String s=sc.nextLine();
        String a=sc.next();
        char f=a.charAt(0);
        String b=sc.next();
        char g=b.charAt(0);
        if(Character.isLetter(f) && Character.isLetter(g)){
            System.out.pritnln("Invalid input");
            return;
        }
        System.out.println(s.replace(a,b));
    }
}