'use strict'

const main = input => {
	const args = input.split('\n').map(arg => arg.split(' '))
	const a = parseInt(args[0][0], 10)
	const b = parseInt(args[0][1], 10)
	const c = parseInt(args[0][2], 10)
	const d = parseInt(args[0][3], 10)
	if (Math.abs(a - c) <= d || (Math.max(Math.abs(a - b), Math.abs(b - c)) <= d)) console.log('Yes')
	else console.log('No')
}

main(require('fs').readFileSync('/dev/stdin', 'utf8'))
