Longest Subarray Without Reapeating in Scala

Given an input array of integers, find the length of the longest subarray without reapeating integers.

Example

Input: nums = [2, 5, 6, 2, 3, 1, 5, 6]
Output: 5
Explanation: [5, 6, 2, 3, 1] or [6, 2, 3, 1, 5] are both valid and of maximum length 5

For this lesson, your algorithm should run in O(n^2) time and use O(n) extra space.
(There exist faster solutions which we will discuss in future lessons)