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Ruby: Sorting 2 arrays using values from one of them

I have an array that looks like this:

a = [[0,1], [1,2], [2,3]]

and an array b like this:

b = [5, 3, 4]

The elements in b correspond to the elements in a on the same index. I want to sort band at the same time the elements in a to change order in the same way as b.

So for the above example I would get:

a = [[1, 2], [2, 3], [0, 1]] and b = [3, 4, 5]

How can I do that?

Answer 1

a = [[0,1], [1,2], [2,3]]
b = [5, 3, 4]
a, b = b.zip(a).sort.transpose
p b #=> [[1, 2], [2, 3], [0, 1]]

To see how this works, just look at the result of p b.zip(a); then p b.zip(a).transpose.