原题地址：https://oj.leetcode.com/problems/set-matrix-zeroes/

题意：Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place.

解题思路：分别记录两个向量x, y，保存行和列是否有0，再次遍历数组时查询对应的行和列然后修改值。

代码：

class Solution:
    # @param matrix, a list of lists of integers
    # RETURN NOTHING, MODIFY matrix IN PLACE.
    def setZeroes(self, matrix):
        rownum = len(matrix)
        colnum = len(matrix[0])
        row = [False for i in range(rownum)]
        col = [False for i in range(colnum)]
        for i in range(rownum):
            for j in range(colnum):
                if matrix[i][j] == 0:
                    row[i] = True
                    col[j] = True
        for i in range(rownum):
            for j in range(colnum):
                if row[i] or col[j]:
                    matrix[i][j] = 0