Submitted by Anonymous (not verified) on Sun, 03/10/2013 - 20:58

Q What can you do with the enum data type?

    A The enum data type can be used to declare names that represent integer constants. You can use the default values held by enum names, or you can assign values to enum names and use them later in the program. The enum data type makes the C program more readable and easier to maintain, because you can use words which you understand as the names of enum, and you will only have to go to one place to update the values when needed.

    Q Why do you need to use the typedef keyword?

    A By using the typedef keyword, you can define your own names to represent the data types in C. You can represent complex data types in a single word and then use that word in subsequent variable declarations. In this way, you can avoid typing errors when writing a complex declaration over and over. Also, if a data type is changed in the future, you just need to update the typedef definition of the data type, which fixes every use of the typedef definition.

    Q Does a recursive function help to improve the performance of a program?

    A Not really. Normally, a recursive function only makes the implementations of some algorithms clearer and simpler. A recursive function may slow down the speed of a program because of the overhead of repeated function calls.

    Q What is the first command-line argument passed to a main() function?

    A The first command-line argument passed to a main() function is the executable filename entered by the user, plus the path to the executable file. The executable file is created from the program that contains the main() function. The first command-line argument is stored in the memory location referenced by the first element in the array of pointers that is declared as the second argument to the main() function.

 

Related Items

Adding More Expressions into for

Adding More Expressions into for

The C language allows you to put more expressions into the three expression fields in the for statement. Expressions in a single expression field are separated by commas.

The Null Statement

The Null Statement

Looping Under the for Statement

Looping Under the for Statement

The general form of the for statement is

for (expression1; expression2; expression3) {
   statement1;
   statement2;
   .
   .
   .
}

Using Nested Loops

Using Nested Loops

You can put a loop inside another one to make nested loops. The computer will run the inner loop first before it resumes the looping for the outer loop.

Listing 7.7 is an example of how nested loops work.

 

The do-while Loop

The do-while Loop

You may note that in the for and while statements, the expressions are set at the top of the loop. However, in this section, you're going to see another statement used for looping,