#include<bits/stdc++.h>
using namespace std;
int main(){
int n,a,b,c,d;
cin>>n;
a=n%10*1000;
b=n/10%10*100;
c=n/100%10*10;
d=n/1000%10*1;
if(n==(a+b+c+d)) cout<<"yes";
else cout<<"no";
}
/**************************************************************
Problem: 1647
User: linmiaoling
Language: C++
Result: Accepted
Time:9 ms
Memory:2072 kb
****************************************************************/