import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in); 
        
        String s = sc.nextLine();
        char[] arr = s.toCharArray();
        
        char c1 = sc.next().charAt(0);
        char c2 = sc.next().charAt(0);
        if(!c1||!c2){
            System.out.println("Invalid input");
            return;
        }
        
        for (int i = 0; i < arr.length; i++) {
            if (arr[i] == c1) {
                arr[i] = c2;
            }
        }
        
        System.out.println(new String(arr));  
    }
}