1646. Get Maximum in Generated Array

You are given an integer `n`. An 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 3.
```

Example 2:

```Input: n = 2
Output: 1
Explanation: According to the given rules, the maximum between nums[0], nums[1], and nums[2] is 1.
```

Example 3:

```Input: n = 3
Output: 2
Explanation: According to the given rules, the maximum between nums[0], nums[1], nums[2], and nums[3] is 2.
```

Constraints:

• `0 <= n <= 100`

1646. Get Maximum in Generated Array
``````struct Solution;

impl Solution {
fn get_maximum_generated(n: i32) -> i32 {
if n == 0 {
return 0;
}
let n = n as usize + 1;
let mut arr = vec![0; n];
arr[0] = 0;
arr[1] = 1;
for i in 2..n {
if i % 2 == 0 {
arr[i] = arr[i / 2];
} else {
arr[i] = arr[i / 2] + arr[i / 2 + 1];
}
}
arr.into_iter().max().unwrap()
}
}

#[test]
fn test() {
let n = 7;
let res = 3;
assert_eq!(Solution::get_maximum_generated(n), res);
let n = 2;
let res = 1;
assert_eq!(Solution::get_maximum_generated(n), res);
let n = 3;
let res = 2;
assert_eq!(Solution::get_maximum_generated(n), res);
}
``````