#!/bin/bash

read A B C D

AC=$(echo $((A-C)) | awk '{print ($1<0)?-$1:$1}')
AB=$(echo $((A-B)) | awk '{print ($1<0)?-$1:$1}')
BC=$(echo $((B-C)) | awk '{print ($1<0)?-$1:$1}')

[ $AC -le $D -o $AB -le $D -a $BC -le $D ] && ANS="Yes" || ANS="No"
echo $ANS