Indexed array declaration in Bash Scripting - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is an indexed array in Bash scripting?

An indexed array in Bash is a list of values stored in a single variable, where each value has a numeric index starting from 0.

beginner

How do you declare an indexed array with values in Bash?

Use syntax: array_name=(value1 value2 value3). For example: fruits=(apple banana cherry).

beginner

How do you access the second element of an indexed array named colors?

Use ${colors[1]} because indexing starts at 0.

intermediate

How to add a new element to an existing indexed array in Bash?

Use syntax: array_name+=(new_value). For example: fruits+=('orange') adds 'orange' to the fruits array.

beginner

What command shows all elements of an indexed array named my_array?

Use echo ${my_array[@]} to print all elements separated by spaces.

How do you declare an indexed array named pets with elements 'dog', 'cat', and 'bird'?

A pets<dog cat bird>

B pets=[dog, cat, bird]

C pets=(dog cat bird)

D pets={dog cat bird}

In Bash, indexed arrays are declared with parentheses and space-separated values.

What is the index of the first element in a Bash indexed array?

A 1

B -1

C Depends on the array

D 0

Bash arrays start indexing at 0, like many programming languages.

How do you print all elements of an indexed array colors?

A echo ${colors[@]}

B echo ${colors[*]}

C echo colors

D echo colors[]

Both ${colors[@]} and ${colors[*]} print all elements, but ${colors[@]} is preferred for separate elements.

How to add 'pear' to an existing array fruits?

A fruits.append('pear')

B fruits+=('pear')

C fruits.push('pear')

D fruits = fruits + 'pear'

In Bash, use += with parentheses to add elements to an array.

Which syntax is correct to access the third element of array numbers?

A ${numbers[2]}

B ${numbers[3]}

C ${numbers(2)}

D ${numbers{2}}

Indexing starts at 0, so the third element is at index 2.

Explain how to declare and access elements in an indexed array in Bash.

Think about how you list items in a shopping list and then pick one by its position.

Describe how to add a new element to an existing indexed array in Bash.

Imagine adding a new item to your list without rewriting the whole list.