#include<iostream> using namespace std; string s1,s2; int main() { cin>>s1; int len=s1.size(); for(int i=0;i<len;i++){ s2[i]=s1[len-1-i]; } bool flag=1; for(int i=0;i<len;i++){ if(s2[i]!=s1[i]){ cout<<"no"; return 0; } } cout<<"yes"; return 0; }