#include<bits/stdc++.h>
using namespace std;
int main(){
	int n,g,s,b,q;
	cin>>n;
	g=n%10;
	s=n/10%10;
	b=n/100%10;
	q=n/1000; 
	if (g==q && s==b){
		cout<<"yes"<<endl;
	}
	else{
		cout<<"no"<<endl;
	}
    return 0;
}

/**************************************************************
	Problem: 1647
	User: xiaojingxuan
	Language: C++
	Result: Accepted
	Time:11 ms
	Memory:2072 kb
****************************************************************/