1646. Get Maximum in Generated Array

#### QUESTION:

You are given an integer n. A 0-indexed integer array nums of length n + 1 is generated in the following way:

nums[0] = 0 nums[1] = 1 nums[2 * i] = nums[i] when 2 <= 2 * i <= n nums[2 * i + 1] = nums[i] + nums[i + 1] when 2 <= 2 * i + 1 <= n Return the maximum integer in the array nums​​​.

Example 1:

``````Input: n = 7
Output: 3
Explanation: According to the given rules:
nums[0] = 0
nums[1] = 1
nums[(1 * 2) = 2] = nums[1] = 1
nums[(1 * 2) + 1 = 3] = nums[1] + nums[2] = 1 + 1 = 2
nums[(2 * 2) = 4] = nums[2] = 1
nums[(2 * 2) + 1 = 5] = nums[2] + nums[3] = 1 + 2 = 3
nums[(3 * 2) = 6] = nums[3] = 2
nums[(3 * 2) + 1 = 7] = nums[3] + nums[4] = 2 + 1 = 3
Hence, nums = [0,1,1,2,1,3,2,3], and the maximum is max(0,1,1,2,1,3,2,3) = 3.
``````

Example 2:

``````Input: n = 2
Output: 1
Explanation: According to the given rules, nums = [0,1,1]. The maximum is max(0,1,1) = 1.
``````

Example 3:

``````Input: n = 3
Output: 2
Explanation: According to the given rules, nums = [0,1,1,2]. The maximum is max(0,1,1,2) = 2.
``````

Constraints:

``````0 <= n <= 100
``````

#### SOLUTION:

``````class Solution {
func getMaximumGenerated(_ n: Int) -> Int {
var arr: [Int] = [0,1]
if n == 0 {
return 0
}
if n == 1 {
return 1
}
for index in 2...n {
if index % 2 == 0 {
arr.append(arr[index/2])
} else {
arr.append(arr[index/2] + arr[index/2+1])
}
}
return arr.max()!
}
}
``````