205.数组中的第k个最大元素

思路：partition函数

class Solution(object):
    def findKthLargest(self, nums, k):
        def partition(low,high):
            pivot = nums[low]
            while low=pivot:
                    high-=1
                nums[low] = nums[high]
                while low t - 1:
                right = idx - 1