334. 递增的三元子序列

LIS

有点杀鸡用牛刀的嫌疑

单调栈

时间复杂性达标, 空间需要O(n)

import sys

class Solution(object):
    def increasingTriplet(self, nums):
        """
        :type nums: List[int]
        :rtype: bool
        """
        
        p_f1 = sys.maxint
        p_f2 = sys.maxint
        
        for n in nums:
          if n > p_f2:
            return True
          
          if n <= p_f1:
            p_f1 = n
          else:
            p_f2 = n
        return False