LeetCode

341. Flatten Nested List Iterator

文章目录
  1. 1. 题目
  2. 2. 思路

题目

https://leetcode.com/problems/flatten-nested-list-iterator/

思路

看到题我的第一反应是用栈来解决，一个个进行pop就行，所以代码如下：

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class NestedIterator(object):

    def __init__(self, nestedList):
        """
        Initialize your data structure here.
        :type nestedList: List[NestedInteger]
        """
        self.stack = []
        self.list = nestedList

    def next(self):
        """
        :rtype: int
        """
        return self.stack.pop()
            
    def hasNext(self):
        """
        :rtype: bool
        """
        while self.list or self.stack:
            if not self.stack:
                self.stack.append(self.list.pop(0))
            while self.stack and not self.stack[-1].isInteger():
                top = self.stack.pop().getList()
                for e in top[::-1]:
                    self.stack.append(e)
            if self.stack and self.stack[-1].isInteger():
                return True
        return False