CSE 130 – Lecture 7 – C Syntax and Variables

Published on: Wed Feb 10 2010

Punctuation in C

Statements are terminated with a “;”
Groups of statements are enclosed by {}
Commas separate function Arguments
White space is ignored
Upper case & Lower case are different

Variables C has 32 keywords. Do not use these 32 keywords as variable names. Char = “A”. Stores in the memory an integer representing the character in the system Unsigned Int = An integer variable that does not reserve a piece of memory for +/- TYPE SIZE HIERARCHY Char | Short > 2 > Int | Unsigned | Long | Float > 4 > Double > 8 Use size() to get the exact size of a variable sizeof(intname) → returns # of bytes used. This is useful for moving from machine to machine A variable can always be stored in a variable of a larger or equal size. If you want to go smaller you must cast. int x = int(3.149) x = 3 ← NOTICE, C truncates, it does not round Conversion Examples float average = 100.0/80.0 = 12.5 float/int = float = 12.5 int/int = int = 12 (lost the decimal point) When doing floating point math include the .0 for whole numbers! Operators in C Arithmetic Operators: + - * / % Logical Operators: && || ! == != && and || or ! not == Equal check != not equal a + b + is the operator a and b are operands x++ post increment ++x pre increment