import java.util.regex.*;
import java.io.*;

public class RegExpSetForCaseSensitive{
	public static void main(String[] args) throws IOException{
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		System.out.print("Enter string: ");
		String string = in.readLine();
		System.out.print("Enter string for search: ");
		String str = in.readLine();
		Pattern pattern = Pattern.compile(str, Pattern.CASE_INSENSITIVE);
		Matcher matcher = pattern.matcher(string);
		String afterReplace = matcher.replaceAll("F");
		System.out.println(afterReplace);
	}
}