#include<stdio.h>

int main(){

  int n;
  scanf("%d",&n);
  
  if(n <= 0){
      printf("Invalid input");
      return 0;
  }
  
  int temp = n;
  int reverse  =0;
  int count = 0;
  int num = 1;
  int number = n;
  
  while(num == 1){
  while(temp != 0){
      int digit = temp % 10;
      count++;
       reverse = (reverse * 10) + digit;
       temp = temp / 10;
  }
  if(n == reverse)
  {
      num = 0;
      printf("%d",num);
  }else{
      number = number + 1;
  }
 
}
printf("%d",reverse);
    return 0;
}