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

#include<atcoder/all>
using namespace atcoder;
using mint=atcoder::modint998244353;

#define int long long

#define rep(i,n) for(int i=0;i<(n);i++)
#define rng(i,l,r) for(int i=(l);i<(r);i++)
#define rrep(i,n) for(int i=(n)-1;i>=0;i--)
#define rrng(i,l,r) for(int i=(r)-1;i>=(l);i--)
#define all(x) (x).begin(),(x).end()
#define pb push_back
#define fi first
#define se second

struct fast_io{fast_io(){cin.tie(nullptr)->sync_with_stdio(false);}}_;
template<class T> bool chmax(T &a,T b){return (a<b)?a=b,1:0;}
template<class T> bool chmin(T &a,T b){return (a>b)?a=b,1:0;}

template<class T>using pqmin=priority_queue<T,vector<T>,greater<T>>;

signed main(){
	string S;cin>>S;
	int a=S[0]-'0',b=S[1]-'0',c=S[2]-'0';
	if(a+c==b)cout<<"Yes\n";
	else cout<<"No\n";
}