How to get the last element of an array in Ruby?

Question

Example:

a = [1, 3, 4, 5]
b = [2, 3, 1, 5, 6]

How do I get the last value 5 in array a or last value 6 in array b without using a[3] and b[4]?

KL-7 · Accepted Answer · 2011-12-26 23:15:57Z

236

Use -1 index (negative indices count backward from the end of the array):

a[-1] # => 5
b[-1] # => 6

a.last # => 5
b.last # => 6

answered Dec 26, 2011 at 23:07

KL-7

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3 Comments

Let's not forget the convenient Array#last, too :) [1,2,3].last #=> 3

@theTinMan Since pop also modifies the array, it's not what was asked for here.

Also that while a.last = 10 #=> NoMethodError: undefined method last=' but a[-1] = 10 works as intended.

Lewis Buckley · Accepted Answer · 2022-10-31 15:50:37Z

13

One other way, using the splat operator:

*a, last = [1, 3, 4, 5]

a => [1, 3, 4]
last => 5

answered Sep 1, 2015 at 10:37

Lewis Buckley

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