#include <bits/stdc++.h>
using namespace std;

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    string s; cin >> s;
    if(s.at(0)-'0'+s.at(2)-'0' == s.at(1)-'0') cout << "Yes\n";
    else cout << "No\n";
}