Divide Array Into Equal Pairs

main.md

Question

Approach

I use a frequency counter to count the occurrences of each number in nums. If every number appears an even number of times, then nums can be divided into valid pairs. Else it's not possible to divide the array into required pairs.

Implementation

class Solution:
    def divideArray(self, nums: List[int]) -> bool:
        count = Counter(nums)
        return all(v % 2 == 0 for v in count.values())

Complexities

• Time: O(n)
• Space: O(n)