#28013: _CPP
11030067@mail.hpsh.tp.edu.tw
(和平110級鄧雨珊)
#include <iostream>
using namespace std;
int main(){
string s1;
while (cin >> s1){
bool p=true;
int len=s1.length();
for (int i=0; i<len/2; i++){
if (s1[i]!=s1[len-i-1]){
p=false;
}
}
if (p){
cout <<"yes"<<endl;
}
else {
cout <<"no"<<endl;
}
}
}