#include <iostream>
using namespace std;
int main()
{
string input;
while (cin >> input) {
for (int i = 0; i < input.length(); i++) {
if (input[i] == input[input.length() - i - 1]) {
cout << "yes" << endl;
break;
}
else
{
cout << "no" << endl;
break;
}
}
}
return 0;
}
hi