program walk_and_teleport
  implicit none
  integer :: n, i
  integer(8) :: a, b, x(100000), s
  x = 0_8
  read(*,*) n, a, b
  read(*,*) x(1:n)
  s = 0
  do i = 1, n-1
    s = s + min(a*(x(i+1)-x(i)),b)
  end do
  write(*,'(i0)') s
  stop
end program walk_and_teleport