[914] X of a Kind in a Deck of Cards

https://leetcode.com/problems/x-of-a-kind-in-a-deck-of-cards/description/

• algorithms
• Easy (33.64%)
• Source Code: 914.x-of-a-kind-in-a-deck-of-cards.py
• Total Accepted: 16.5K
• Total Submissions: 48.2K
• Testcase Example: '[1,2,3,4,4,3,2,1]'

In a deck of cards, each card has an integer written on it.

Return true if and only if you can choose X >= 2 such that it is possible to split the entire deck into 1 or more groups of cards, where:

Each group has exactly X cards.
All the cards in each group have the same integer.

Example 1:

Input: [1,2,3,4,4,3,2,1] Output: true Explanation: Possible partition [1,1],[2,2],[3,3],[4,4]

Example 2:

Input: [1,1,1,2,2,2,3,3] Output: false Explanation: No possible partition.

Example 3:

Input: [1] Output: false Explanation: No possible partition.

Example 4:

Input: [1,1] Output: true Explanation: Possible partition [1,1]

Example 5:

Input: [1,1,2,2,2,2] Output: true Explanation: Possible partition [1,1],[2,2],[2,2]

Note:

1 <= deck.length <= 10000
0 <= deck[i] < 10000

class Solution(object):
    def hasGroupsSizeX(self, deck):
        """
        :type deck: List[int]
        :rtype: bool
        """
        table = {}
        for d in deck:
            if d not in table:
                table[d] = 0
            table[d] += 1

        g = reduce(self.gcd, table.values())
        if g < 2: return False

        return True

    def gcd(self, a, b):
        if b != 0:
            return self.gcd(b, a %  b)
        return a