program yukicoder_401
  use, intrinsic :: iso_fortran_env
  implicit none
  integer(int32) :: n, y, x, next_y, next_x, direction
  integer(int32), allocatable :: grids(:, :)
  integer(int32) :: i
  read(input_unit, *) n
  allocate(grids(0:n+1, 0:n+1), source = -1)
  grids(0, :) = huge(0_int32)
  grids(:, 0) = huge(0_int32)
  grids(n + 1, :) = huge(0_int32)
  grids(:, n + 1) = huge(0_int32)
  y = 1; x = 1
  direction = 1
  do i = 1, n * n
     grids(y, x) = i
     ! write(error_unit, *) grids(1:n, 1:n)
     select case(direction)
     case(1) !> EAST.
        if (grids(y, x + 1) > 0) then
           direction = 2
           y = y + 1
        else
           x = x + 1
        end if
     case(2) !> SOUTH.
        if (grids(y + 1, x) > 0) then
           direction = 3
           x = x - 1
        else
           y = y + 1
        end if
     case(3) !> WEST.
        if (grids(y, x - 1) > 0) then
           direction = 4
           y = y - 1
        else
           x = x - 1
        end if
     case(4) !> NORTH.
        if (grids(y - 1, x) > 0) then
           direction = 1
           x = x + 1
        else
           y = y - 1
        end if
     end select
  end do
  do i = 1, n
     write(output_unit, '(*(i3.3, 1x))') grids(i, 1:n)
  end do
end program yukicoder_401