Today's Challenge

https://leetcode.com/problems/132-pattern

132 Pattern - LeetCode

이것도 뒤에서 부터 순회하면서 스텍 사용해서 풀면 됨

class Solution:
    def find132pattern(self, nums: List[int]) -> bool:
        if len(nums)<3:
            return False
      
        second_num = -math.inf
        stck = []
        
        for i in range(len(nums) - 1, -1, -1):
            if nums[i] < second_num:
                return True
            while stck and stck[-1] < nums[i]:
                second_num = stck.pop()
                
            stck.append(nums[i])
        return False