R5-矩阵篇

印象题，思路即可：

手动置0

无非就是行和列都置0

使用thex和they将该元素的i和y存储起来，再分别遍历thex，将所有y的位置置0

遍历they，将所有x 置0

class Solution:
    def setZeroes(self, matrix: List[List[int]]) -> None:
        """
        Do not return anything, modify matrix in-place instead.
        """
        m=len(matrix)
        n=len(matrix[0])
        thex=[]
        they=[]
        for i in range(m):
            for j in range(n):
                if matrix[i][j]==0:
                    thex.append(i)
                    they.append(j)
        #清除
        for i in thex:
            for j in range(n):
                matrix[i][j]=0
        
        for j in they:
            for i in range(m):
                matrix[i][j]=0