import java.util.*;

class MiroirLettres {

    public static void main(String args[]) {
        String chaine = "this is a test";
	Stack pile = new Stack();
        for (int i=0; i<chaine.length(); i++) {
            pile.push(new Character(chaine.charAt(i)));
	}
	while(!pile.isEmpty()) {
	    System.out.print(pile.pop());
	}
	System.out.println();
    }
}