Practical C++ Programming by manish baranwal

The old C language provides the program with two types of function parameters: “call by value” and

“array.” (Pointers are used to get around the limitations of “call by value.”)

C++ provides you with lots of new parameter and return types. These include constant and reference

parameters and return values.

Next there is a quick overview of structure programming (top-down programming) and bottom-up

programming. One thing to emphasize is that there have been a lot of different programming

methodologies introduced over the years. Each has its own band of fanatics who support it above all

others. Each has proved that although it is useful, it is not the ultimate programming system.

The current design fad is called “Object Oriented Design.” We get into this later when we get into

classes. “Object Oriented Design” is not the ultimate programming system. This too will pass.

Ideally, what you should teach your students is that there are a lot of programming techniques out there

and the programmer should pick the one that allows him to best organize his program. Don’t blindly

follow the rules if there is some way to make your program clearer and easier to maintain.

Finally, we introduce the tricky subject of recursion. The idea of calling a function from within itself is

foreign to some people. But I’ve programmed in LISP using no looping statements, and you’d be

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amazed at what you can do recursively when you’re forced to.

Recursion is very simple actually. You just need to remember the two rules:

1. It must have an ending point.

2. It must make the problem simpler.

Live Demonstration

Slide 3 scope/scope.cpp

Slide 6 perm/perm.cpp

Slide 25 length/length.cpp

Classroom Presentation Suggestions

Use the debugger to step through the program on Slide 3 and set watch points for the variables global,

local, and very_local. If you do this right, you will start out with our “watch” window looking

like:

global 0

local <variable out of scope>

very_local <variable out of scope>

(Some debuggers don’t allow you to insert a watch for a variable that is not currently active. In this case

you need to single-step to the middle of the program, set watches on all the variables and restart. This

will prepare your program for the students.)

Step through the program on Slide 6. Emphasize the fact that the statement

int temporary = 1;

constructs and initializes the variable. This will come in handy when classes are discussed. Also, the

variable is destroyed at the end of the block. Using the words “construction” and “destruction” will help

relate this material to the class constructor and destructor member functions.