# 73. Set Matrix Zeroes """ given an 'm x n' integer 'matrix', if an element is '0', set its entire row and columns to '0's. you must do it in place """ class Solution(object): def setZeroes(self, matrix): """ :type matrix: List[List[int]] :rtype: None Do not return anything, modify matrix in-place instead. """ r, c = 0, 0 for i in range(len(matrix)): for j in range(len(matrix[i])): if matrix[i][j] == 0: r |= 1 << i c |= 1 << j for i in range(len(matrix)): for j in range(len(matrix[i])): if r & 1 << i or c & 1 << j: matrix[i][j] = 0 if __name__ == "__main__": obj = Solution() m1 = [[1, 1, 1], [1, 0, 1], [1, 1, 1]] m2 = matrix = [[0, 1, 2, 0], [3, 4, 5, 2], [1, 3, 1, 5]] obj.setZeroes(m1) obj.setZeroes(m2) print(m1) print(m2)