#include <iostream>
#include <cstring>
#include <cstdio>
#include <algorithm>
using namespace std;
const int N = 1000 + 5;
int a[N];
int main()
{
   int a,b,c,d;
   while(cin >> a >> b >> c >> d)
   {
       int fl = 0;
       if(abs(a-c) <= d) fl = 1;
       if(abs(b-a) <= d && abs(c-b) <= d) fl = 1;
       if(fl == 1)
        printf("Yes\n");
       else
        printf("No\n");
   }
}
