program problem
  implicit none
  integer :: floor = 0
  integer :: steps = 0
  character(len=:), allocatable :: input
  integer :: input_file_size, unit, i

  open(newunit=unit, file='../data/2015/1/input.txt', access="stream")
    inquire(unit=unit, size=input_file_size)
    allocate(character(len=input_file_size) :: input)

    read(unit) input

    do i=1, input_file_size
       if (input(i:i) == "(") then
          floor = floor + 1
       else
          floor = floor - 1
       end if
    end do
    print *, "Part 1: ", floor

    floor = 0
    do i=1, input_file_size
       if (input(i:i) == "(") then
          floor = floor + 1
       else
          floor = floor - 1
       end if
       steps = steps + 1
       if (floor < 0) exit
    end do
    print *, "Part 2: ", steps

  close(1)
end program problem