U3: Arrays

• Has index starting from 0 and increment by 1 • Index is reference to location of item

• Can only store data all of same type • Ex: Integers, Strings

• Must be done same way as variables • Camel notation if name has +2 words • Ex: studentMarks, cardValues

Programmer should know and state (vertical) size of array before using

• Declare name, size and type of data stored • Ex: int [ ] exampleName = new int [6]; for 0 to 5

int [ ] values = new int [2]; values [0] = 3; values [1] = 71;

Double [ ] avg = {34.7, 54.3, 8.9}

• int [ ] numbers = new int [1]; • numbers[0] = keyedInput.nextInt();

Possible

• Can only output one value at time • Ex: System.out.println(values[0]); System.out.println(values[1]);

Actual data stored in array cell

Location/index value where element located

Highest and lowest indexes (0 to [size - 1])

• i++: i = i + 1 • i–: i = i - 1

• Odd: variable % 2 = 1 • Even: variable % 2 = 0

• int[ ] List = new int[5]; • int[ ] List2 = List;

variable.length