// editor3
import java.util.*;
public class main{
    public static void main(String []args){
        Scanner sc = new Scanner(System.in);
        String str = sc.nextLine();
        if(hasNextChar()){
            char fst = sc.next().charAt(0);
        }else{
            System.out.println("Invalid input");
        }
        
        
        if(hasNextChar()){
            char cst = sc.next().charAt(0);
        }else{
            System.out.println("Invalid input");
        }
        
       
        int size=str.length();
        String a="";
        
        for(int i=0;i<size;i++){
            char b=str.charAt(i);
            if(b == fst){
                a=a+cst;
            }else{
                a=a+b;
            }
        }
        System.out.println(a);
    }
}