CS214-C Programming Notes Pensacola Christian College

CS 214 - C Programming Notes
Author: Mali Payani
Lecturer: Dr Jonathan Sparks

CS 214 - Lecture 1- CH. 2
Intro to the C Language

Background:
 Core programming language

Why C?
 Powerful
 Syntax similar to other languages
 Structured high-level language
 Efficient
 Reusable through libraries
 Mature and wide accepted

C's History:
Timeline:
 1960s- ALGOL (Algorithm)
 1967- BCPL (Martin Richards) Basically Combined Programming Language
 1970- B Language (Ken Thompson)
 1972- C language (Dennis Ritchie)
 1989- ANSI C standardization
 1999- Major C standard update
 2011- Minor C Update

Basic Parts of a Program:
1. Preprocessor Directives
2. Global Declarations
3. Local Declarations
4. Statements
5. Other Functions

,CS 214 - Lecture 2
Steps to Program:
The basic steps are:
1. Understand: understanding what the problem is will help us to find a solution.
2. Plan (Risk Analysis): finding a solution (flow charts).
3. Code: Implementation
4. Compile
5. Test
6. Implement: Publishing app to the public
 Don't forget to documentation. Documentation is for other coders.

Error Types:
 Syntax
 Prevents a program from compiling
 Error message may help solve these.
 Misspelling, punctuation, spacing
 Logic (a problem with the implementation)
 Prevents a program from running properly.
 More subtle (painful)-the joy of programming
 Example: Start at 1, count by 2's until counter equals 100.
 Programs can run with logic errors.
 Testing is important here.

#Page 32

Comments
 Describes a function or code block's purpose.
 Block comment: /* text*/
 Line Comments: // (1999 Standard)
 Don't overuse.
 Can appear anywhere a space can but cannot be nested.

Structure of a C Program: pg. 32
 Preprocessor Directives
 Global Directives
 Local Directives
 Statements
 Other functions as required

Preprocessor Directives (like a to-do list):
#include <stdio.h>
- Tells the compiler to do something before compiling.
- Appears at the beginning of the code.
- Begins with a '#'

,CS 214 - Lecture 3
 #include includes a header file or library (like java's 'import')
 Appendix G-pg. 1071: writing your own libraries
 Line the # all the way to the lef
 No space between # and 'include'
 stdio- standard input/output: allows user to write on the screen (printf function)
What are Libraries?
 Additional features (mostly functions) which can be available to the program.
 C is a small language-libraries extend it as needed. ex. #include <stdio.h>
 Standard libraries are available for all. <stdio.h>; printf
o Standard libraries available: Appendix F - pg. 1059
 Programmers can create their own so that they themselves or other programmers can access it.

The main() function
 int main(void) /*int returns an integer value. It is not required
to type void. All it means is it doesn't receive anything as it's
running.*/
{
declaration section
statement section
}

 A main() is required!
 The program begins and ends with main()
 It calls other functions.

The printf() Function:
 printf() is a standard library function from <stdio.h>
 You cannot use the printf without <stdio.h>
 This library is used for most programs.
 Items between parentheses of a function are called parameters or arguments.
ex. printf("Hello world!"); // the string is the parameter or argument.

printf() Control Codes:
 "escape sequences" are used for special things.
 Control codes begin with a '\'
 List of codes: pg. 48
 Carriage return returns to next line.

Variable Identifiers:
 Name referring to a place in memory where data or objects can be stored or a box that holds something.
 A variable has a:
o Name
o Type
o Value
o Address

,  Using a variable name accesses the value stored at that memory location.

Identifier Naming: see pg. 37
 First character must be alphabetical character or underscore
 Must consist only of alphabetical characters, digits, or underscores.
 First 63 characters of an identifier are significant.
 Cannot duplicate a keyword.




CS 214 - Lecture 4