Zero matrix

zero_matrix_1_8.py

#!/usr/bin/env python

# Zero matrix
# Write an algorithm such that if an element in a MxN matrix is 0, its entire row and column are set
# to 0

import copy

class ZeroMatrix:
  def __init__(self, matrix):
    self.matrix = matrix
    self.matrix_len = len(matrix)

  def run(self):
    result = copy.deepcopy(self.matrix)
    zero_x_index_list = []
    zero_y_index_list = []
    for i, row in enumerate(self.matrix):

      for j, ele in enumerate(row):
        if ele == 0:
          zero_x_index_list.append(i)
          zero_y_index_list.append(j)
          for x in range(self.matrix_len):
            result[i][x] = 0
            result[x][j] = 0
        elif i in zero_x_index_list or j in zero_y_index_list:
          continue;
        else:
          result[i][j] = ele

    return result

  def print_matrix(self, matrix):
    return "\n".join([str(m) for m in matrix])



if __name__ == '__main__':
  matrix = \
      [
          [ 1, 2, 3, 4, 0, 6, 7],
          [ 1, 2, 3, 4, 5, 6, 7],
          [ 1, 2, 3, 4, 5, 6, 7],
          [ 1, 0, 3, 4, 5, 6, 7],
          [ 1, 2, 3, 4, 0, 6, 7],
          [ 1, 2, 3, 4, 5, 6, 7],
          [ 1, 2, 3, 4, 5, 6, 7],
      ]
  zero_matrix = ZeroMatrix(matrix)
  result = zero_matrix.run()

  print "INPUT"
  print zero_matrix.print_matrix(matrix)
  print "OUTPUT"
  print zero_matrix.print_matrix(result)