function main(arg) {
	arg = arg.split("\n").map(Number)
	var k = arg[5]
	var data = [
		arg[0],arg[1],arg[2],arg[3],arg[4]
	]
	var flag = true
	for (var i  = 0; i < data.length; i++) {
		for (var j = i + 1; j < data.length; j++) {
			var ans = Math.abs(data[j] - data[i])
			// console.log(ans)
			if (ans > k) {
				flag = false
			}
		}
	}
	if (flag) {
		console.log('Yay!')
	} else {
		console.log(':(')
	}
	// console.log(data)
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));