High Level

Low Level

Specific Subroutines

Executive Subroutine

Top

Down

main()

screen()

box()

setup()

input()

printer()

kill()

picture()

In this case we see that most of the routines are at the bot-

tom of the design tree. This structure shows a clear

enter()

division of tasks, to their basic parts. On the above dia-

gram, none of the functions calls any of the functions

to the left of it, only to the right. In this case main() will

draw_line()

call setup(), screen(), input() and kill() directly.

text()

calculations()