#include <bits/stdc++.h>

using namespace std;

int AB(int x)
{
    return x < 0? (-x) : x;
}
int ac, ab, bc, a, b, c, d;
int main()
{
    ac = 0; ab = 0; bc = 0;
    scanf("%d%d%d%d", &a, &b, &c, &d);
    if (AB(a-c) <= d) ac = 1;
    if (AB(a-b) <= d) ab = 1;
    if (AB(b-c) <= d) bc = 1;
    if (ac == 1 || (ab == 1 && bc == 1)) cout<<"Yes\n"; else cout<<"No\n";
}
