import java.util.*;
import java.lang.*;
import java.io.*;

class Ideone {
  public static void main (String[] args) {
  	String value = String.valueOf(312123991239L);
    Arrays.stream(digitize(value)).forEach(System.out::print);
  }
	
  static int[] digitize(String value) {
  	String reversed = new StringBuilder(value).reverse().toString();
    return Arrays.stream(reversed.split(""))
      .mapToInt(Integer::parseInt)
      .toArray();
  }
}