2811. Check if it is Possible to Split Array

Problem Link

Description

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You are given an array nums of length n and an integer m. You need to determine if it is possible to split the array into n arrays of size 1 by performing a series of steps.

An array is called good if:

• The length of the array is one, or
• The sum of the elements of the array is greater than or equal to m.

In each step, you can select an existing array (which may be the result of previous steps) with a length of at least two and split it into two arrays, if both resulting arrays are good.

Return true if you can split the given array into n arrays, otherwise return false.

 

Example 1:

Input: nums = [2, 2, 1], m = 4

Output: true

Explanation:

• Split [2, 2, 1] to [2, 2] and [1]. The array [1] has a length of one, and the array [2, 2] has the sum of its elements equal to 4 >= m, so both are good arrays.
• Split [2, 2] to [2] and [2]. both arrays have the length of one, so both are good arrays.

Example 2:

Input: nums = [2, 1, 3], m = 5

Output: false

Explanation:

The first move has to be either of the following:

• Split [2, 1, 3] to [2, 1] and [3]. The array [2, 1] has neither length of one nor sum of elements greater than or equal to m.
• Split [2, 1, 3] to [2] and [1, 3]. The array [1, 3] has neither length of one nor sum of elements greater than or equal to m.

So as both moves are invalid (they do not divide the array into two good arrays), we are unable to split nums into n arrays of size 1.

Example 3:

Input: nums = [2, 3, 3, 2, 3], m = 6

Output: true

Explanation:

• Split [2, 3, 3, 2, 3] to [2] and [3, 3, 2, 3].
• Split [3, 3, 2, 3] to [3, 3, 2] and [3].
• Split [3, 3, 2] to [3, 3] and [2].
• Split [3, 3] to [3] and [3].

 

Constraints:

• 1 <= n == nums.length <= 100
• 1 <= nums[i] <= 100
• 1 <= m <= 200

Solution

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Python3

class Solution:
    def canSplitArray(self, nums: List[int], m: int) -> bool:
        N = len(nums)
        
        if N <= 2: return True
        
        for i in range(1, N):
            if nums[i] + nums[i - 1] >= m:
                return True
        
        return False