LeetCode 刷题 6. Z 字形变换

题目链接点此

思路：根据他要求的行数，创建一个多维数组，然后再以如0123210的等顺序循环给这个多维数组的行赋值，最后将一行行取值拼接即可

class Solution:
    def convert(self, s: str, numRows: int) -> str:
        if numRows<=1 or len(s)<=1:
            return s
        i = 0
        a = 1
        lis = [[] for _ in range(numRows)]
        for l in range(len(s)):
            if i==0:
                a=1
            if i==numRows-1:
                a=-1
            lis[i].append(s[l])
            i+=a
        li2 = ''.join(str(item) for innerlist in lis for item in innerlist)
        return li2