Zigzag Iterator

这道题主要注意列指针跳的时候的情况，另外也可以用generator来实现，但是个人觉得用迭代器实现迭代器其实算作弊了，不符合出题者的意图

class ZigzagIterator(object):

    def __init__(self, v1, v2):
        """
        Initialize your data structure here.
        :type v1: List[int]
        :type v2: List[int]
        """
        self.nestedVector = [v1, v2]
        self.curRow = 0
        self.curCol = 0

    def next(self):
        """
        :rtype: int
        """
        result = self.nestedVector[self.curRow][self.curCol]
        if self.curRow:
            self.curCol += 1
            self.curRow = 0
        else:
            self.curRow += 1
        return result

    def hasNext(self):
        """
        :rtype: bool
        """
        if self.curCol >= len(self.nestedVector[self.curRow]):
            if self.curRow:
                self.curRow = 0
                self.curCol += 1
            else:
                self.curRow = 1
        return self.curCol < len(self.nestedVector[self.curRow])


# Your ZigzagIterator object will be instantiated and called as such:
# i, v = ZigzagIterator(v1, v2), []
# while i.hasNext(): v.append(i.next())