#include<iostream>
#include<algorithm>
using namespace std;

int main(){
    int a,b,c,d;
    cin>>a>>b>>c>>d;
    int e=c-a;
    if(e<0)
        e=-e;
    int f=c-b;
    int g=b-a;
    if(e<=d)
        cout<<"Yes"<<endl;
    else if(f<=d&&g<=d)
        cout<<"Yes"<<endl;
    else
        cout<<"No"<<endl;
    return 0;
}
