Podcast
Questions and Answers
What is the purpose of including a library in a C program?
What is the purpose of including a library in a C program?
What symbol is used at the end of a standard header file in C?
What symbol is used at the end of a standard header file in C?
.h
A pair of angle brackets is used to open a predefined library.
A pair of angle brackets is used to open a predefined library.
True
What directive gives a program access to a library?
What directive gives a program access to a library?
Signup and view all the answers
What type of constant is represented by the value 'A'?
What type of constant is represented by the value 'A'?
Signup and view all the answers
How are integer constants specified?
How are integer constants specified?
Signup and view all the answers
String constants are enclosed by single quotes.
String constants are enclosed by single quotes.
Signup and view all the answers
What is the purpose of the #define directive?
What is the purpose of the #define directive?
Signup and view all the answers
What keyword is used for local constant declarations in C?
What keyword is used for local constant declarations in C?
Signup and view all the answers
The first section of a C program is called the ______.
The first section of a C program is called the ______.
Signup and view all the answers
What is the typical return value of the main function in a C program?
What is the typical return value of the main function in a C program?
Signup and view all the answers
Study Notes
C Library
- C libraries are collections of functions and symbols that a program can access.
- Libraries offer several operations that programs can use.
- The standard header file for a C library ends with ".h".
- To open a predefined library, use angle brackets (<>).
- To open a user-defined library, use double quotes ("").
#include Directive
- Gives a program access to a library.
- Tells the preprocessor to insert definitions from a standard header file into the program.
- The preprocessor modifies the code before compilation.
- It also informs the preprocessor about names used in the program that are found in the standard header file.
C Constants
- These fixed values remain unchanged during program execution.
- Types of constants:
- Character constants: Enclosed in single quotes (e.g., 'A', '+').
- Integer constants: Whole numbers without fractional components (e.g., 5, -160).
- Floating constants: Numbers with decimal points followed by fractional components (e.g., 16.234).
- String constants: Sets of characters enclosed in double quotes (e.g., "bag", "this is good").
- Backslash character constants: Single-quoted character constants, used for characters that require special handling (e.g., 't' for tab).
CONSTANTS
- Constants are data values that cannot be modified during a program's execution.
- Constants have a specific type.
- Two ways to define them:
- Using the preprocessor (#define): A global declaration used to assign macro constant values.
-
Using the
constkeyword: A local declaration, usually within a function.
#define
- Allows text substitution within a program before compilation.
- Identifiers intended for preprocessor replacement are conventionally written in uppercase letters.
Using #define
- Multiple data types can be defined using #define:
- #define SCORE 100 (integer)
- #define PI 3.14159 (float)
- #define code ‘A’ (character)
- #define MSSG “Hello” (string)
Using the const keyword
- Declare constants within a function.
- Examples:
-
const char MSSG = “Hello”;(character) -
const float PI = 3.1459;(float) -
const int year = 2024;(integer) -
const code = ‘X’;(character)
-
General Structure of a C Program
- Each C program consists of two sections:
-
Heading section: Includes preprocessor directives, which typically start with
#. - Executable section: Contains the program's logic, written as code enclosed in curly braces.
-
Heading section: Includes preprocessor directives, which typically start with
- Common elements:
-
#include <stdio.h>: Includes the standard input-output library, essential for functions likeprintfandscanf. -
int main(void): The main function, the starting point of every C program. -
return 0;: Indicates successful execution of the program. - Comments: Explanatory text that is ignored by the compiler (often using
//or/* ... */).
-
Sample C Program
- Contains the
#include <stdio.h>directive for using input-output operations. - Demonstrates the
int main()function. - Includes a placeholder
printf...for potential code within the function.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz covers important concepts regarding C libraries, including the use of the #include directive and different types of constants in C programming. Test your understanding of how libraries function and the significance of constants in code execution.
