import std.stdio;
import std.conv;
import std.string;
import std.typecons;
import std.algorithm;
import std.array;
import std.range;
import std.math;
import std.regex : regex;
import std.container;
import std.bigint;


void main()
{
  auto x = readln.chomp.split.to!(int[]);
  
  if (abs(x[0] - x[2]) <= x[3] || 
     (abs(x[0] - x[1]) <= x[3] && abs(x[1] - x[2]) <= x[3])) {
    writeln("Yes");
  } else {
    writeln("No");
  }
}
