split_array_into_consecutive_subsequences.py

class Solution(object):
    def isPossible(self, nums):
        """
        :type nums: List[int]
        :rtype: bool
        """
        count = collections.Counter(nums)
        tails = collections.Counter()
        for num in nums:
            if count[num] == 0:
                continue
            elif tails[num] > 0:
                tails[num] -= 1
                tails[num + 1] += 1
            elif count[num + 1] > 0 and count[num + 2] > 0:
                count[num + 1] -= 1
                count[num + 2] -= 1
                tails[num + 3] += 1
            else:
                return False
            count[num] -= 1
        return True