How to compare two arrays and get index in the form of an array?

How to compare two arrays and get index in the form of an array?

Here are two arrays:

arrayOne = [a, b, d, g, k]     arrayTwo = [a, b, c, d, e, f, g, h, i, j, k]

Since these two arrays have some elements in common, I want to get the index of [a, b, d, g, k] in arrayTwo, and then put those index to an array. Is there any way to do it?