main = do
	a <- readLn
	b <- readLn
	c <- readLn
	d <- readLn
	e <- readLn
	k <- readLn
    if all (distance k) ls
    then print "Yay!"
    else print ":("
    where ls = [ b - a
    		   , c - a
    		   , d - a
    		   , e - a
    		   , c - b
    		   , d - b
    		   , e - b
    		   , d - c
    		   , e - c
    		   , e - d
               ]
    
distance k d =
	if abs d <= k
   	then true
    else false