#include<iostream>
#include<cmath>
using namespace std;
int main()
{   int a,b,c,d;
   while(cin>>a>>b>>c>>d){
     int flag=0;
     if(abs(c-a)<=d){
            cout<<"Yes"<<endl;
            continue;
     }
     if(abs(a-b)<=d&&abs(b-c)<=d){
        cout<<"Yes"<<endl;
        continue;
     }

     cout<<"No"<<endl;

   }

return 0;

}
