README.md

805. Split Array With Same Average

You are given an integer array nums.

You should move each element of nums into one of the two arrays A and B such that A and B are non-empty, and average(A) == average(B).

Return true if it is possible to achieve that and false otherwise.

Note that for an array arr, average(arr) is the sum of all the elements of arr over the length of arr.

Example 1:

Input: nums = [1,2,3,4,5,6,7,8]
Output: true
Explanation: We can split the array into [1,4,5,8] and [2,3,6,7], and both of them have an average of 4.5.

Example 2:

Input: nums = [3,1]
Output: false

Constraints:

• 1 <= nums.length <= 30
• 0 <= nums[i] <= 104

Solutions (Python)

1. Solution

class Solution:
    def splitArraySameAverage(self, nums: List[int]) -> bool:
        if len(nums) < 2:
            return False

        s = sum(nums)
        sums = [set() for _ in range(len(nums) // 2 + 1)]
        sums[0].add(0)

        for num in nums:
            for i in range(len(sums) - 2, -1, -1):
                for x in sums[i]:
                    if (x + num) * len(nums) == s * (i + 1):
                        return True

                    sums[i + 1].add(x + num)

        return False