#include <iostream>
#include <string>
#include <vector>

int main() {
    std::string clovo;
    std::getline(std::cin, clovo);

    int a = 0;
    int b = clovo.size() - 1;
    bool yesOrNo = true;

     while (a < b) {
        if (clovo[a] == ' ') {
            ++a;
        } else if (clovo[b] == ' ') {
            --b;
        } else if (clovo[a] != clovo[b]) {
            yesOrNo = false;
            break;
        } else {
            ++a;
            --b;
        }
    }

    if (yesOrNo) {
        std::cout << "YES\n";
    } else {
        std::cout << "NO\n";
    }
}