Palindrome

#include<iostream>
#include<string>
using namespace std;
int main(){
string s;
cin>>s;
int b=0;
for(int i=0;i<s.size();i++){if(s[i]!=s[s.size()-i-1])

{b=1;
break;}
}
if(b==0){
    cout<<"yes";
}
else cout<<"N0";
    }