import java.lang.Math.abs

fun main(args:Array<String>) {
	val v = readLine()!!.split(" ").map{ it.toInt() }
	if(abs(v[0]-v[2])<=v[3] || abs(v[0]-v[1])<=v[3] && abs(v[1]-v[2])<=v[3]) {
		println("Yes")
	}else{
		println("No")
	}
	
}