题目

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

解析

根据题意生成数组,然后返回最大值即可.

代码

C++

class Solution {
public:
    int getMaximumGenerated(int n) {
        if (!n) return 0;
        int arr[101] = {0, 1};
        for (int i = 2; i <= n; ++i)
            arr[i] = i % 2 ? arr[i / 2] + arr[i / 2 + 1] : arr[i / 2];
        int size = sizeof(arr) / sizeof(arr[0]);
        return *max_element(arr, arr + size);
    }
};