Basic Codes

Basic Format

/* header comments */

preprocessor directives

main function heading

{

variable declarations

executable statements

return statement

}

other function definitions (optional)

/* sample output */

Preprocessor directives

#include <stdio.h>

#define NAME #

Main function heading

int main (void)

Variable Declarations

float variable names;

• variable names only allow letters (abc), digits (123), underscores (_).

• DONT start with #

• DONT use reserved words

Executable Statements

printf(“statement”);

printf("That equals %f kilometers.\n", kms);

• kms outside quotation marks replaces %f inside

scan(“%f”, &variable_name);

• stores input as float, as the variable.

Assignment Statements: assigns a variable a value

variable name = value

Return Statement (for the end)

return (0);

printf Format Specifiers

%c single character (ASCII) 'X'

%d, %i signed integer (CAREFUL with %i for input)

%e, %E floating point, e-notation (E-notation: 8.16532e-11)

%g, %G floating point, decimal or e-notation (E-notation)

%f floating point, decimal notation

%s character string

%u unsigned integer

%x, %X unsigned hexadecimal integer (A,B,...)

%o unsigned octal integer

%p pointer (memory address)

%% percent sign

Escape Sequences (backslashes /)

\n new line

\t tab

\f form feed (new page)

\r carriage return (go back to column 1)

\b backspace

\\ backslash character

\" double quote

\' single quote