How to match 2 arrays and get an output in new array Ruby

Question

Let's say i have 2 arrays with the same length filled with integers

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

And i want to compare these arrays and get an output in new (c) array so it would look like this

c = [+,-,+,-]

If there will be 0 matches then my new array would give [-,-,-,-] and vice versa in case of 4 matches [+,+,+,+]

[+,-,+,-] isn't valid Ruby syntax. What kind of objects should the new array contain – strings, symbols or maybe booleans? — Stefan
– Stefan, Commented Jun 9, 2021 at 10:20

Lam Phan · Accepted Answer · 2021-06-09 09:27:18Z

1

a.each_with_index.map {|x, i| b[i] == x ? '+' : '-'}

answered Jun 9, 2021 at 9:27

Lam Phan

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Comments

Stefan · Accepted Answer · 2021-06-09 10:29:56Z

1

You can use zip to get pairs from both arrays which can then be converted via map, e.g.:

a.zip(b).map { |i, j| i == j }
#=> [true, false, true, false]

to get "+" and "-" instead you'd use:

a.zip(b).map { |i, j| i == j ? '+' : '-' }
#=> ["+", "-", "+", "-"]

answered Jun 9, 2021 at 10:22

Stefan

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