#include<iostream> #include<cstring> //字符串的头文件 using namespace std; string s; int main(){ cin>>s; int len1 = s.length(); for(int i=0;i<len1/2;i++){ if(s[i]!=s[len1-1]){ cout<<"No"<<endl; return 0; } } cout<<"Yes"<<endl; return 0; }