'use strict'

const main = input => {
	const args = input.split('\n').map(arg => arg.split(' '))
	const a = parseInt(args[0][0], 10)
	const e = parseInt(args[4][0], 10)
	const k = parseInt(args[5][0], 10)
	if (e - a <= k) console.log('Yay!')
	else console.log(':(')
}

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