#include<iostream>
#include<string>
#include<algorithm>
using namespace std;

int main(){
  string s;
  cin >> s;
  
  string reversed = s;
  reverse(reversed.begin(), reversed.end());
  
  if(s == reversed){
    cout << "YES";
  }
  else{
    cout << "NO";
  }
  
  return 0;
}