Arrays - Day 3

Question 1

Initialising the array

Answer 1

Datatype[] arrayVarName = {elem1e,elem2};

Datatype[] arrayVarName = new dataType[size];

Question 2

Locating array index

Answer 2

Arrayvarname[index]

Question 3

Arrays are objects?

Answer 3

Yes

Question 4

Unlike python, arrays are pretty restricted and can only hold 1 data type

Answer 4

True

Question 5

For loop in array for elements

Answer 5

For (int index = 0; index < arrayName.length; index++) {

}

Question 6

For each loops

Answer 6

Splits up each element, no use of indexing

For(dataType variableName: arrayName){

}

Question 7

Multi dimensional arrays

Answer 7

Each element of the array holding other arrays.

For a 2D array:

Datatype[][] arrayVarName = new dataType[rowsize][columnsize];

Row is length of array
Column is array of each array element

Columnsize is optional

Question 8

When a value isn’t initialised in an array. What happens

Answer 8

It saves the value as zero/defaults.

Question 9

Command line arguments

Answer 9

Inputs passed into the program through the command line

Question 10

How to use command line

Answer 10

Need the parameter

“String[] args” in the main

Question 11

Input through command line example

Answer 11

System.out.printIn(“hello” +args[0]):

NOT TESTED for exam. WILL USE SCANNER