#include using namespace std; typedef long long ll; const int MOD=1000000007; #define INF 1LL<<30 #define rep(i,n) for (int i = 0; i < (n); ++i) #define all(x) (x).begin(),(x).end() int main(){ ll a,b,c,d; cin>>a>>b>>c>>d; if(a*a-2*a*c+c*c==8*b-8*d){ cout<<"Yes"<