#include<iostream>

using namespace std;
int main()
{
    int a,b,c,d;
    cin>>a>>b>>c>>d;
    int s1 = c-b;
    int s2 = a-d;
    if(s1<s2){
        cout<<"Yes"<<endl;
    }
    if(s1>s2){
        cout<<"No"<<endl;
    }



    return 0;
}

