For Dummies Beginning Programming with C++ 978-0-470-61797-7 User Manual
Product codes
978-0-470-61797-7
11
Chapter 1: What Is a Program?
On the other hand, humans are very good at certain types of processing that
computers do poorly, if at all. For example, humans are very good at pulling
the meaning out of a sentence garbled by large amounts of background noise.
By contrast, digital cell phones have the infuriating habit of just going silent
whenever the noise level gets above a built-in threshold.
computers do poorly, if at all. For example, humans are very good at pulling
the meaning out of a sentence garbled by large amounts of background noise.
By contrast, digital cell phones have the infuriating habit of just going silent
whenever the noise level gets above a built-in threshold.
Programming a “Human Computer”
Before I dive into showing you how to write programs for computer con-
sumption, I start by showing you a program to guide human behavior so
that you can better see what you’re up against. Writing a program to guide a
human is much easier than writing programs for computer hardware because
we have a lot of familiarity with and understanding of humans and how they
work (I assume). We also share a common human language to start with. But
to make things fair, assume that the human computer has been instructed
to be particularly literal — so the program will have to be very specific. Our
guinea pig computer intends to take each instruction quite literally.
sumption, I start by showing you a program to guide human behavior so
that you can better see what you’re up against. Writing a program to guide a
human is much easier than writing programs for computer hardware because
we have a lot of familiarity with and understanding of humans and how they
work (I assume). We also share a common human language to start with. But
to make things fair, assume that the human computer has been instructed
to be particularly literal — so the program will have to be very specific. Our
guinea pig computer intends to take each instruction quite literally.
The problem I have chosen is to instruct our human computer in the chang-
ing of a flat tire.
ing of a flat tire.
The algorithm
The instructions for changing a flat tire are straightforward and go something
like the following:
like the following:
1. Raise the car.
2. Remove the lug nuts that affix the faulty tire to the car.
3. Remove the tire.
4. Mount the new tire.
5. Install the lug nuts.
6. Lower the car.
(I know that technically the lug nuts hold the wheel onto the car and not the
tire, but that distinction isn’t important here. I use the terms “wheel” and
“tire” synonymously in this discussion.)
tire, but that distinction isn’t important here. I use the terms “wheel” and
“tire” synonymously in this discussion.)
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