Fruit into Baskets

Medium

Question

You're given an array of integers that represent a single line of trees with one fruit, where each integer value represents the type of fruit.

Your objective is to collect as much fruit as possible while following these conditions:

You can only pick fruit starting from left to right
You only have two baskets to hold two different types of fruits
When you reach a third type of fruit that can't be put into your baskets, you must stop picking altogether
There is no limit to the amount of fruit each basket can hold

Return the maximum number of fruit you can pick.

Input: [1, 0, 2, 2, 1, 2]

Output: 4

We can pick from trees [2, 2, 1, 2]. If we had started at the first tree, we would only pick from trees [1, 0]. If we had started at the second tree, we would only pick from trees [0, 2, 2].

Input: [1, 2, 1]

Output: 3

We can pick from all three trees.

Input: [2, 4, 3, 4, 4]

Output: 4

We can pick from trees [4, 3, 4, 4]. If we had started at the first tree, we would only pick from trees [2, 4].