Accessing elements (indexing, first, last) in Ruby - Cheat Sheet & Quick Revision

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beginner

How do you access the first element of an array in Ruby?

Use the first method. For example, array.first returns the first element.

beginner

What does array[-1] return in Ruby?

It returns the last element of the array. Negative indices count from the end, so -1 is the last element.

beginner

How can you access the third element of an array named arr?

Use zero-based indexing: arr[2] returns the third element because counting starts at zero.

beginner

What method returns the last element of an array in Ruby?

The last method returns the last element. For example, array.last.

beginner

What happens if you try to access an index that is out of range in Ruby arrays?

Ruby returns nil if the index is outside the array bounds, instead of an error.

Which Ruby code returns the first element of an array named nums?

A nums[1]

B nums.first

C nums.last

D nums[-1]

nums.first returns the first element. nums[1] returns the second element because indexing starts at zero.

What does arr[-2] return?

A Second element from the end

B First element

C Last element

D Second element from the start

Negative indices count from the end. -1 is last, so -2 is second from the end.

How do you get the last element of an array list?

A list.last

B list.first

C list[0]

D list[1]

list.last returns the last element of the array.

What will array[10] return if array has only 5 elements?

A The 11th element

B An error

C The last element

D nil

Ruby returns nil when accessing an index outside the array bounds.

Which index accesses the third element in a Ruby array?

A 1

B 3

C 2

D -3

Ruby arrays use zero-based indexing, so index 2 is the third element.

Explain how to access the first, last, and a specific element in a Ruby array.

Think about methods and index numbers.

What happens if you try to access an array element with an index that is too large?

Consider Ruby's behavior with out-of-range indices.