program programik
	integer            :: a, h
    real               :: base_area, side_area, total_area
   	integer, parameter :: out_unit = 20
    logical            :: continue_flag = .TRUE.
    character(LEN=3)   :: continue_input

	open(unit=out_unit,file="results.txt",action="write",status="append")

	do while (continue_flag)
    	a = 0
        h = 0
		do while ( a <= 0 )
    		write(*,*) "Podaj dlugosc boku podstawy!"
        	read(*,*) a
	   	end do
    	do while ( h <= 0 )
    		write(*,*) "Podaj wysokosc!"
        	read(*,*) h
   		end do
    	! Wzor na podstawe trojkata rownobocznego
    	base_area = a * a * sqrt(3.0) / 4
    	! Wzor na pole boczne ostroslupa prawidlowego trojkatnego
    	side_area = 3.0 * a * h / 2
    	! Pole calkowite
    	total_area = base_area + side_area

    	write(*,*) base_area
    	write(*,*) side_area
    	write(*,*) total_area
		write(out_unit,*) base_area, side_area, total_area

        write(*,*) "Jezeli chcesz kontynuowac wpisz tak"
        read(*,*) continue_input
        if (continue_input == "tak") then
          continue_flag = .TRUE.
        else
          continue_flag = .FALSE.
        end if

	end do

	close(out_unit)
end program