396. Rotate Function LeetCode Solution

In this guide, you will get 396. Rotate Function LeetCode Solution with the best time and space complexity. The solution to Rotate Function problem is provided in various programming languages like C++, Java, and Python. This will be helpful for you if you are preparing for placements, hackathons, interviews, or practice purposes. The solutions provided here are very easy to follow and include detailed explanations.

Problem Statement
Complexity Analysis
Rotate Function solution in C++
Rotate Function solution in Java
Rotate Function solution in Python
Additional Resources

396. Rotate Function LeetCode Solution image

Problem Statement of Rotate Function

You are given an integer array nums of length n.
Assume arrk to be an array obtained by rotating nums by k positions clock-wise. We define the rotation function F on nums as follow:

F(k) = 0 * arrk[0] + 1 * arrk[1] + … + (n – 1) * arrk[n – 1].

Return the maximum value of F(0), F(1), …, F(n-1).
The test cases are generated so that the answer fits in a 32-bit integer.

Example 1:

Input: nums = [4,3,2,6]
Output: 26
Explanation:
F(0) = (0 * 4) + (1 * 3) + (2 * 2) + (3 * 6) = 0 + 3 + 4 + 18 = 25
F(1) = (0 * 6) + (1 * 4) + (2 * 3) + (3 * 2) = 0 + 4 + 6 + 6 = 16
F(2) = (0 * 2) + (1 * 6) + (2 * 4) + (3 * 3) = 0 + 6 + 8 + 9 = 23
F(3) = (0 * 3) + (1 * 2) + (2 * 6) + (3 * 4) = 0 + 2 + 12 + 12 = 26
So the maximum value of F(0), F(1), F(2), F(3) is F(3) = 26.

Example 2:

Input: nums = [100]
Output: 0

Constraints:

n == nums.length
1 <= n <= 105
-100 <= nums[i] <= 100

Complexity Analysis

Time Complexity: O(n)
Space Complexity: O(1)

396. Rotate Function LeetCode Solution in C++

class Solution {
 public:
  int maxRotateFunction(vector<int>& nums) {
    const int sum = accumulate(nums.begin(), nums.end(), 0);
    int f = 0;

    // Calculate F(0) first.
    for (int i = 0; i < nums.size(); ++i)
      f += i * nums[i];

    int ans = f;

    for (int i = nums.size() - 1; i > 0; --i) {
      f += sum - nums.size() * nums[i];
      ans = max(ans, f);
    }

    return ans;
  }
};
/* code provided by PROGIEZ */

396. Rotate Function LeetCode Solution in Java

class Solution {
  public int maxRotateFunction(int[] nums) {
    final int sum = Arrays.stream(nums).sum();
    int f = 0;

    // Calculate F(0) first.
    for (int i = 0; i < nums.length; ++i)
      f += i * nums[i];

    int ans = f;

    for (int i = nums.length - 1; i >= 0; --i) {
      f += sum - nums.length * nums[i];
      ans = Math.max(ans, f);
    }

    return ans;
  }
}
// code provided by PROGIEZ

396. Rotate Function LeetCode Solution in Python

class Solution:
  def maxRotateFunction(self, nums: list[int]) -> int:
    f = sum(i * num for i, num in enumerate(nums))
    ans = f
    summ = sum(nums)

    for a in reversed(nums):
      f += summ - len(nums) * a
      ans = max(ans, f)

    return ans
 # code by PROGIEZ