#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";
    }
    else{
        cout<<"NO";
    }
}