Ruby convert array to hash using array index as keys

Question

How can I transform the array ["a","b","c","d"] into a hash where the key equals the array index + 1. {1 => "a", 2 => "b", 3 => "c", 4 => "d"}

Arup Rakshit · Accepted Answer · 2015-03-27 12:53:39Z

5

Here is my work :

(1..a.size).zip(a)
# => [[1, "a"], [2, "b"], [3, "c"], [4, "d"]]
(1..a.size).zip(a).to_h
# => {1=>"a", 2=>"b", 3=>"c", 4=>"d"}

answered Mar 27, 2015 at 12:53

Arup Rakshit

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2 Comments

Oh, nice! I was going to suggest ["a","b","c","d"].each.with_index(1).to_a.map(&:reverse).to_h or something, but this is much cleaner.

@Ajedi32 Another was a.each_index.with_object({}) { |i, h| h[i+1] = a[i] }... :D

sawa · Accepted Answer · 2015-03-27 12:52:53Z

3

["a","b","c","d"]
.each.with_index(1).with_object({}){|(e, i), h| h[i] = e}
# => {1=>"a", 2=>"b", 3=>"c", 4=>"d"}

answered Mar 27, 2015 at 12:52

sawa

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