program main

  implicit none

  integer    :: n
  integer,allocatable :: x(:)

  integer    :: i, j, mdmin, md

  read(*,*) n
  allocate( x(n) )
  read(*,*) x
  
  do i = 1, 100
    md = 0

    do j = 1, n
      md =  md + ( x(j) - i )**2
    end do

    if( i == 1 ) then
       mdmin = md
    else
      if( mdmin > md ) then
       mdmin = md
      end if
    end if

  end do
  print*, mdmin
  
  !call quicksort1( p, 1, int( n*(n-1) )+1 ) 
  !call quicksort1( p, 1, n*(n-1)/2 ) 

  !print*, p(k)

end program main

recursive subroutine quicksort1(a, first, last)
  implicit none
  integer(8),intent(inout)::a(*)
  integer,intent(in)::first,last
  !
  ! Original
  ! https://gist.github.com/t-nissie/479f0f16966925fa29ea
  !
  integer(8)::x,t
  integer::i,j

  x = a((first+last)/2)
  i = first
  j = last
  do
     do while (a(i) < x)
        i=i+1
     end do
     do while (x < a(j))
        j=j-1
     end do
     if (i >= j) exit
     t = a(i)
     a(i) = a(j)
     a(j) = t
     i=i+1
     j=j-1
  end do
  if (first < i-1) call quicksort1(a, first, i-1)
  if (j+1 < last)  call quicksort1(a, j+1, last)

  return
end subroutine quicksort1
