How to find the intersection of n arrays in Ruby?

Question

[1, 2, 3] & [2, 3, 4] gives us [2, 3] but how do you get the intersection of n arrays?

[[1, 2, 3], [2, 3, 4], [1, 3, 4]].something would give [3]

Looping with & works but there must be a better way.

Arup Rakshit · Accepted Answer · 2013-04-30 16:56:24Z

8

[[1, 2, 3], [2, 3, 4], [1, 3, 4]].inject(:&) #=> [3]

answered Apr 30, 2013 at 16:56

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Comments

Data Don · Accepted Answer · 2013-07-08 10:31:32Z

Just & all arrays. Suppose you have 3 arrays.

a = [1,2,3] b = [2,3,4] c = [3,4,5] a & b & c => [3]