import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
int n = scan.nextInt();
int a = 0;
int b = 0;
int c = 0;
int d = 0;
for(int i = 1; i <= 4; i++) {
a = n / 1000;
b = n / 100 % 10;
c = n / 10 % 10;
d = n % 10;
}
System.out.printf("%d%d%d%d", d, c, b, a);
}
}