Arithmetic Expressions Addition (+) Subtraction (-) Multiplication (*) Division (/) –Integer –Real Number Mod Operator (%) Same as regular Depends on the types of the operands involved. Remainder operator

Order of Operations Same as math class –() –*, /, % –+, - Here’s an example: –3 + 4*5 - 6/3*4/8 + 2*6 - 4*3*2 – – 24 –10

Integer Division If the two operands are of type int, then integer division occurs An integer division truncates (chops off) any fractional part of the answer. Examples –13/4 = 3 –7/8 = 0 –19/3 = 6

Real Number Division If at least one of the two operands is a double (or float), then a real number division occurs Examples –13/4.0 = 3.25 –13.0/4.0 = 3.25 –19.0/5 = 3.8

Other Issues with Division Variable on the left-hand side of an assignment is of type int, while the expression on the right is a real number –val = 8/5.0, will set val to 1, if val is an int. If the variable on the left-hand side is a double, but the expression on the right is an int, the variable gets set to an int. –val = 8/5, will set val to 1, if val is a double.

Mod Operator A % B returns the remainder when A is divided by B, and A and B MUST BE ints! Examples –12%5 = 2 –19%6 = 1 –14%7 = 0 –19%200 = 19

Initializing Variables If you declare a variable without a value, then that variable initially could equal anything Usually, it’s a good practice to give your variables initial values. Examples –int sum = 0, value = 1; –double price = 0.0;

Defining Constants Use #define Examples –#define FEET_IN_YARD 3 –#define PI Benefits –Code is Easier to Read –If a constant needs to be “changed”, you only need to change it at the top of your program. (ie. if you find out that some program parameter has changed)