program main
	implicit none
	integer N
    integer(8) ans
	integer, allocatable :: a(:)
	read(*, *) N
	allocate(a(1:N))
	read(*, *) a(1:N)
	ans = 0
	do i = 1, N
		ans = ans + a(i) - 1
	end do
	write(*, *) ans
end program main