Basic Anticheat (FORTRAN)

program anticheat
  implicit none

  character(len=20) :: cheats(3) = ['cheat1', 'cheat2', 'cheat3']
  character(len=20) :: input
  logical :: isCheating

  ! Prompt the user for input
  write(*,'(A)') 'Enter a command: '
  read(*,'(A)') input

  ! Check if the user is cheating
  isCheating = .false.
  do i = 1, 3
    if (index(input, cheats(i)).ne.0) then
      isCheating = .true.
      exit
    end if
  end do

  ! If the user is cheating, display a message and exit the program
  if (isCheating) then
    write(*,'(A)') 'Cheating is not allowed!'
    stop
  end if

  ! If the user is not cheating, continue with the program
  write(*,'(A)') 'Valid input'
end program anticheat