module mod_priority_queue
  implicit none
  type t_priority_queue
    private
    integer :: num = 0
    integer, pointer :: heap(:) => null()
  contains
    procedure :: offer => offer
    procedure :: clear => clear
    procedure :: poll => poll
    procedure :: peek => peek
    procedure :: size => size_of
  end type
contains
  integer function compare(a,b)
    integer, intent(in) :: a, b
    compare = a-b
  end
  subroutine offer(this,item)
    class(t_priority_queue), intent(inout) :: this
    integer, intent(in) :: item
    integer :: n, i, t
    integer, allocatable :: tmp(:)
    if (.not.associated(this%heap)) allocate(this%heap(1))
    if (this%num == size(this%heap)) then
      allocate(tmp(this%num))
      tmp = this%heap
      deallocate(this%heap)
      allocate(this%heap(2*this%num))
      this%heap(1:this%num) = tmp
      deallocate(tmp)
    end if
    this%num = this%num+1
    this%heap(this%num) = item
    n = this%num
    do while (n > 1)
      i = n/2
      if (compare(this%heap(n),this%heap(i)) < 0) then
        t = this%heap(n)
        this%heap(n) = this%heap(i)
        this%heap(i) = t
      end if
      n = i
    end do
  end
  subroutine clear(this)
    class(t_priority_queue), intent(inout) :: this
    if (associated(this%heap)) deallocate(this%heap)
    this%num = 0
  end
  function poll(this) result(item)
    class(t_priority_queue), intent(inout) :: this
    integer :: item, n, i, j, tmp
    n = this%num
    item = this%heap(1)
    this%heap(1) = this%heap(n)
    this%num = this%num-1
    i = 1
    do while (2*i < n)
      j = 2*i
      if (j+1 < n .and. compare(this%heap(j+1),this%heap(j)) < 0) j = j+1
      if (compare(this%heap(j),this%heap(i)) < 0) then
        tmp = this%heap(j)
        this%heap(j) = this%heap(i)
        this%heap(i) = tmp
      end if
      i = j
    end do
  end
  function peek(this) result(item)
    class(t_priority_queue), intent(in) :: this
    integer :: item
    item = this%heap(1)
  end
  integer function size_of(this)
    class(t_priority_queue), intent(in) :: this
    size_of = this%num
  end
end module mod_priority_queue
program integer_cards
  use mod_priority_queue
  implicit none
  integer :: n, m, a(100000) = 0, b(100000,2) = 0, i, j, t
  integer(8) :: x = 0
  type(t_priority_queue) :: pq
  read(*,*) n, m
  read(*,*) a(1:n)
  do i = 1, n
    call pq%offer(a(i))
  end do
  do i = 1, m
    read(*,*) b(i,:)
  end do
  call merge_sort(b(1:m,:))
  do i = 1, m
    do j = 1, b(i,1)
      if (b(i,2) <= pq%peek()) goto 100
      t = pq%poll()
      call pq%offer(b(i,2))
    end do
  end do
  100 do i = 1, n
    x = x+pq%poll()
  end do
  write(*,'(i0)') x
contains
  subroutine merge_sort(a)
    integer, intent(inout) :: a(:,:)
    integer :: n, m, l, i, u
    n = size(a,1)
    m = n
    l = 1
    do while (m > 1)
      do i = 1, m/2
        u = min(2*i*l,n)
        call merger(a(2*(i-1)*l+1:(2*i-1)*l,:),a((2*i-1)*l+1:u,:))
      end do
      l = 2*l
      m = (m+1)/2
    end do
  end
  subroutine merger(a1,a2)
    integer, intent(inout) :: a1(:,:), a2(:,:)
    integer :: a(size(a1,1)+size(a2,1),size(a1,2))
    integer :: i1, i2, n1, n2
    i1 = 1
    i2 = 1
    n1 = size(a1,1)
    n2 = size(a2,1)
    do while (i1 <= n1 .and. i2 <= n2)
      if (a1(i1,2) >= a2(i2,2)) then
        a(i1+i2-1,:) = a1(i1,:)
        i1 = i1+1
      else
        a(i1+i2-1,:) = a2(i2,:)
        i2 = i2+1
       end if
    end do
    if (i1 <= n1) then
      a(i1+i2-1:n1+n2,:) = a1(i1:n1,:)
    else
      a(i1+i2-1:n1+n2,:) = a2(i2:n2,:)
    end if
    a1 = a(1:n1,:)
    a2 = a(n1+1:n1+n2,:)
  end
end program integer_cards

Measured memory_bytes: 3284