A Simple C Program

/* Latihan. 2.1: lat02_01.c A first program in C */ #include <stdio.h> int main() { printf( "Welcome to C!\n" ); return 0; }

Welcome to C!

• Comments

- Text surrounded by /* and */ is ignored by computer
- Used to describe program

• #include <stdio.h>

- Preprocessor directive
* Tells computer to load contents of a certain file
- <stdio.h> allows standard input/output operations

• int main()

- C++ programs contain one or more functions, exactly one of which must be main
- Parenthesis used to indicate a function
- int means that main "returns" an integer value
- Braces ( { and } ) indicate a block
* The bodies of all functions must be contained in braces

• printf( "Welcome to C!\n" );

- Instructs computer to perform an action
* Specifically, prints the string of characters within quotes (" ")
- Entire line called a statement
* All statements must end with a semicolon (;)
- Escape character (\)
* Indicates that printf should do something out of the ordinary
* \n is the newline character

• return 0;

- A way to exit a function
- return 0, in this case, means that the program terminated normally

• Right brace }

- Indicates end of main has been reached

• Linker

- When a function is called, linker locates it in the library
- Inserts it into object program
- If function name is misspelled, the linker will produce an error because it will not be able to find function in the library