program sample
	implicit none
    integer(8)::i,j
    real(8)::a,b,c,d,e,k,sub
    real(8) :: sort(5)
    
    read(*,*) a
    read(*,*) b  
    read(*,*) c    
    read(*,*) d    
    read(*,*) e    
    read(*,*) k 
    
    sort(1) =a
    sort(2) =b
    sort(3)=c
    sort(4)=d
    sort(5)=e
    
    do i=1,5
    	do j=i,5
        	if(sort(i)>sort(j)) then
            	sub=sort(i)
                sort(i)=sort(j)
                sort(j)=sub
            end if
        end do
    end do
    
    if(abs(sort(5)-sort(1))<=k) then
    	write(*,*) 'Yay!'
	else
    	write(*,*) ':('
    end if
    
    stop
end program sample