programming-for-dummies

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Creating Functions
If you don’t know how many times you need to repeat commands, you’ll
have to use a WHILE loop, which looks like this:
while (condition) {
Command;
}
If the condition is True, the loop runs at least once. If this condition is
False, the loop does not run.
A variation of the WHILE loop is the DO-WHILE loop, which looks like this:
do {
Command;
} while (condition);
The main difference between the two loops is that the WHILE loop may run
zero or more times, but the DO-WHILE loop always runs at least once.
Somewhere inside a WHILE and a DO-WHILE loop, you must have a command
that can change the condition from True to False; otherwise, the
loop will never end, and your program will appear to hang or freeze.
Creating Functions
In C/C++, every subprogram is a function that can return a value. The format
of a typical function looks like this:
Datatype functionname (Parameter list)
{
Commands;
Return value;
}
The three parts of a C/C++ function are
✦ Data type: Defines the type of value the function returns, such as an
integer (int) or a floating point number (float). If you don’t want a
function to return a value, declare its data type as void. This makes the
function act like a procedure in other programming languages.
✦ Parameter list: Defines any data and their data types that the function
needs to work.
✦ Return: Defines a value to return. This value must be the same data type
specified right before the function name.