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

 

    /// <summary>
    /// Write an algorithm such that if an element in an MxN matrix is 0, its entire row and column is set to 0.
    /// </summary>
    class Program
    {
        static void Main(string[] args)
        {
            Program p = new Program();
            int[,] matrix = new int[3, 4] { { 1, 2, 3, 4 }, { 5, 6, 7, 0 }, { 9, 10, 11, 0 } };
            p.SetColumnAndRowWithZeroWhileElementIsZero(ref matrix);
            PrintMatrix(matrix);
            Console.ReadKey();
        }

        public void SetColumnAndRowWithZeroWhileElementIsZero(ref int[,] matrix)
        {
            int line = matrix.GetLength(0);
            int column = matrix.GetLength(1);
            if (line == 0 || column == 0)
            {
                return;
            }

            int[] rows = new int[line];
            int[] colums = new int[column];

            //mark the row or column which will be set to zero
            for (int i = 0; i < line; i++)
            {
                for (int j = 0; j < column; j++)
                {
                    if (matrix[i, j] == 0)
                    {
                        rows[i] = 1;
                        colums[j] = 1;
                    }
                }
            }

            for (int i = 0; i < line; i++)
            {
                for (int j = 0; j < column; j++)
                {
                    if (rows[i] == 1 || colums[j] == 1)
                    {
                        matrix[i, j] = 0;
                    }
                }
            }
        }
        /// <summary>
        /// Print the matrix to console
        /// </summary>
        public static void PrintMatrix(int[,] matrix)
        {
            int line = matrix.GetLength(0);
            int column = matrix.GetLength(1);
            if (line == 0 || column == 0)
            {
                Console.WriteLine("empty array!");
            }
            else
            {
                Console.WriteLine("lines:" + line.ToString());
                Console.WriteLine("columns:" + column.ToString());
            }
            for (int i = 0; i < line; i++)
            {
                Console.WriteLine();
                for (int j = 0; j < column; j++)
                {
                    Console.Write(matrix[i, j].ToString().PadLeft(5));
                    Console.Write(" ");
                }
            }
        }
    }