Problem:
Score : 400 points

Problem Statement

Given is a number sequence A of length N.

Find the number of integers i \left(1 \leq i \leq N\right) with the following property:

For every integer j \left(1 \leq j \leq N\right) such that i \neq j , A_j does not divide A_i.

Constraints

All values in input are integers.

1 \leq N \leq 2 \times 10^5

1 \leq A_i \leq 10^6

Input

Input is given from Standard Input in the following format:

N
A_1 A_2 \cdots A_N

Output

Print the answer.

Sample Input 1

5
24 11 8 3 16

Sample Output 1

3

The integers with the property are 2, 3, and 4.

Sample Input 2

4
5 5 5 5

Sample Output 2

0

Note that there can be multiple equal numbers.

Sample Input 3

10
33 18 45 28 8 19 89 86 2 4

Sample Output 3

5

Solution in Fortran (GNU Fortran 9.2.1) (judge verdict: Wrong Answer)

module merge_sort_mod
    use,intrinsic :: iso_fortran_env
    implicit none
    private
    public:: merge_sort, double_merge_sort
    interface merge_sort
        module procedure ms32, ms64
    end interface

    interface double_merge_sort
        module procedure msd3232, msd6464
    end interface

contains
    recursive subroutine ms32(ar, fst, lst)
        integer(int32),intent(inout):: ar(:)
        integer(int32),intent(in):: fst,lst
        integer(int32):: mdl

        if (lst-fst < 2) then
            if (ar(fst) > ar(lst)) call swap32(ar(fst),ar(lst))
            return
        end if

        mdl = (fst+lst)/2
        call ms32(ar, fst, mdl)
        call ms32(ar, mdl+1, lst)
        call merge32(ar, fst, mdl, lst)
    end subroutine


    subroutine merge32(ar, fst, mdl, lst)
        integer(int32),intent(inout):: ar(:)
        integer(int32),intent(in):: fst, mdl, lst
        integer(int32),allocatable:: tmp(:)
        integer(int32):: li, ri, ti

        allocate(tmp(lst-fst+1))

        li=fst
        ri=mdl+1   
        ti=1

        do while (li <= mdl .and. ri <= lst)
            if (ar(li) <= ar(ri)) then
                tmp(ti) = ar(li)
                li=li+1
            else
                tmp(ti) = ar(ri)
                ri=ri+1
            end if
            ti=ti+1
        end do

        if (li <= mdl) then
            tmp(ti:) = ar(li:mdl)
        else
            tmp(ti:) = ar(ri:lst)
        end if

        ar(fst:lst) = tmp(:)
        deallocate(tmp)
    end subroutine


    subroutine swap32(x,y)
        integer(int32),intent(inout):: x,y
        integer(int32):: tmp
        tmp = x
        x = y
        y = tmp
    end subroutine


    recursive subroutine ms64(ar, fst, lst)
        integer(int64),intent(inout):: ar(:)
        integer(int64),intent(in):: fst,lst
        integer(int64):: mdl

        if (lst-fst < 2) then
            if (ar(fst) > ar(lst)) call swap64(ar(fst),ar(lst))
            return
        end if

        mdl = (fst+lst)/2
        call ms64(ar, fst, mdl)
        call ms64(ar, mdl+1, lst)
        call merge64(ar, fst, mdl, lst)
    end subroutine


    subroutine merge64(ar, fst, mdl, lst)
        integer(int64),intent(inout):: ar(:)
        integer(int64),intent(in):: fst, mdl, lst
        integer(int64),allocatable:: tmp(:)
        integer(int64):: li, ri, ti

        allocate(tmp(lst-fst+1))

        li=fst
        ri=mdl+1   
        ti=1

        do while (li <= mdl .and. ri <= lst)
            if (ar(li) <= ar(ri)) then
                tmp(ti) = ar(li)
                li=li+1
            else
                tmp(ti) = ar(ri)
                ri=ri+1
            end if
            ti=ti+1
        end do

        if (li <= mdl) then
            tmp(ti:) = ar(li:mdl)
        else
            tmp(ti:) = ar(ri:lst)
        end if

        ar(fst:lst) = tmp(:)
        deallocate(tmp)
    end subroutine


    subroutine swap64(x,y)
        integer(int64),intent(inout):: x,y
        integer(int64):: tmp
        tmp = x
        x = y
        y = tmp
    end subroutine

    recursive subroutine msd3232(ar1, ar2, fst, lst)
        integer(int32),intent(inout):: ar1(:),ar2(:)
        integer(int32),intent(in):: fst,lst
        integer(int32):: mdl

        if (lst - fst < 2) then
            if (ar1(fst) > ar1(lst)) then
                call swap32(ar1(fst), ar1(lst))
                call swap32(ar2(fst), ar2(lst))
            end if
            return
        end if

        mdl = (fst+lst)/2

        call msd3232(ar1,ar2,fst,mdl)
        call msd3232(ar1,ar2,mdl+1,lst)
        call merged3232(ar1,ar2,fst,mdl,lst)
    end subroutine


    subroutine merged3232(ar1,ar2,fst,mdl,lst)
        integer(int32),intent(inout):: ar1(:),ar2(:)
        integer(int32),intent(in):: fst,mdl,lst
        integer(int32),allocatable:: t1(:),t2(:)
        integer(int32):: li,ri,ti

        allocate(t1(lst-fst+1), t2(lst-fst+1))

        li=fst
        ri=mdl+1
        ti=1

        do while(li <= mdl .and. ri <= lst)
            if (ar1(li) <= ar1(ri)) then
                t1(ti) = ar1(li) 
                t2(ti) = ar2(li)
                li=li+1
            else
                t1(ti) = ar1(ri)
                t2(ti) = ar2(ri)
                ri=ri+1
            end if
            ti=ti+1
        end do

        if (li <= mdl) then
            t1(ti:) = ar1(li:mdl)
            t2(ti:) = ar2(li:mdl)
        else
            t1(ti:) = ar1(ri:lst)
            t2(ti:) = ar2(ri:lst)
        end if

        ar1(fst:lst) = t1(:)
        ar2(fst:lst) = t2(:)

        deallocate(t1,t2)
    end subroutine


    recursive subroutine msd6464(ar1, ar2, fst, lst)
        integer(int64),intent(inout):: ar1(:),ar2(:)
        integer(int64),intent(in):: fst,lst
        integer(int64):: mdl

        if (lst - fst < 2) then
            if (ar1(fst) > ar1(lst)) then
                call swap64(ar1(fst), ar1(lst))
                call swap64(ar2(fst), ar2(lst))
            end if
            return
        end if

        mdl = (fst+lst)/2

        call msd6464(ar1,ar2,fst,mdl)
        call msd6464(ar1,ar2,mdl+1,lst)
        call merged6464(ar1,ar2,fst,mdl,lst)
    end subroutine


    subroutine merged6464(ar1,ar2,fst,mdl,lst)
        integer(int64),intent(inout):: ar1(:),ar2(:)
        integer(int64),intent(in):: fst,mdl,lst
        integer(int64),allocatable:: t1(:),t2(:)
        integer(int64):: li,ri,ti

        allocate(t1(lst-fst+1), t2(lst-fst+1))

        li=fst
        ri=mdl+1
        ti=1

        do while(li <= mdl .and. ri <= lst)
            if (ar1(li) <= ar1(ri)) then
                t1(ti) = ar1(li) 
                t2(ti) = ar2(li)
                li=li+1
            else
                t1(ti) = ar1(ri)
                t2(ti) = ar2(ri)
                ri=ri+1
            end if
            ti=ti+1
        end do

        if (li <= mdl) then
            t1(ti:) = ar1(li:mdl)
            t2(ti:) = ar2(li:mdl)
        else
            t1(ti:) = ar1(ri:lst)
            t2(ti:) = ar2(ri:lst)
        end if

        ar1(fst:lst) = t1(:)
        ar2(fst:lst) = t2(:)

        deallocate(t1,t2)
    end subroutine
end module

program main
    use,intrinsic :: iso_fortran_env
    use merge_sort_mod
    implicit none
    integer(int64):: n,i,div,b,ans,cnt(1000000)=0
    integer(int64), allocatable:: a(:)
    logical:: ng(1000000) = .false., ok(1000000) = .true., ook

    read*, n
    allocate(a(n))
    read*, a(:)

    call merge_sort(a,1_8,n)
    ans = 0
    do i=1,n
        b = a(i)
        cnt(b)=cnt(b)+1
        ng(b) = .true.
        div=2
        ook = .true.
        do while(div**2 <= b)
            do while(mod(b,div)==0)
                b=b/div
                if (ng(b) .or. ng(div)) then
                    ook = .false.
                end if
            end do
            div=div+1
        end do
    ! print*, i, ok(i)
        ok(a(i)) = ook
        if (ook) ans=ans+1
    end do

    if (cnt(1) == 1) then
        print'(i0)', 1
    else if (cnt(1) > 1) then
        print'(i0)', 0
    else
        do i=1,1000000
            if (cnt(i) > 1 .and. ok(i)) then
                ! print*, ans, cnt(i)
                ans=ans-cnt(i)
            end if
        end do

        print'(i0)', ans
    end if
end program main