#include <iostream>
#include <string>
using namespace std;
 
int main() {
	string s;
    char c;
    while (cin >> c)
    {
        if (c != ' ') 
        	s.push_back(c);
    }
    if (s.empty())
    {
        cout << "YES";
        return 0;
    }
    bool palindrom = true;
    for (int i = 0; i <= s.length()/2; i++)
    {
        if (s.at(i) != s.at(s.length()-1-i))
        {
            palindrom = false;
            break;
        }
    }
    cout << (palindrom ? "YES" : "NO");
	return 0;
}