Maximum Median Sum of Subsequences of Size 3 — Python

# Time:  O(nlogn)
# Space: O(1)

# sort, greedy
class Solution(object):
    def maximumMedianSum(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        nums.sort()
        return sum(nums[i] for i in xrange(len(nums)//3, len(nums), 2))