Given an array of n elements and elements are  from 1 to n-1. that is

Code

        public static void PrintDuplicate(int[] input)
        {
            int length = input.Length;
            Console.WriteLine(string.Join(";", input));
            for (int i = 0; i < length; i++)
            {
                if (input[Math.Abs(input[i])] >= 0)
                {
                    input[Math.Abs(input[i])] = -input[Math.Abs(input[i])];

                }
                else
                {
                    Console.WriteLine("duplicate number {0} and it's index is {1} ",
                                        Math.Abs(input[i]), i + " ; ");
                }
            }

        }

Today We will write a program for converting matrix’s row and columns to zero if any one element is zero.

Example

Code

        public static void RowColumnZero(int[,] matrix)
        {
            Console.WriteLine("------------------------------------------------------");
            Console.WriteLine("Before");
            Print2DMatrix(matrix);
            int rowConter;
            int columnCounter;

            rowConter = columnCounter = 0;
            int[] rowArray = new int[matrix.GetLength(0)];
            int[] columnArray = new int[matrix.GetLength(1)];

            for (rowConter = 0; rowConter < rowArray.Length; rowConter++)
            {

                for (columnCounter = 0; columnCounter < columnArray.Length; 
                                                        columnCounter++)
                {
                    if (matrix[rowConter, columnCounter] == 0)
                    {
                        rowArray[rowConter] = 1;
                        columnArray[columnCounter] = 1;
                    }
                }
            }


            for (rowConter = 0; rowConter < rowArray.Length; rowConter++)
            {
                for (columnCounter = 0; columnCounter < columnArray.Length; 
                                        columnCounter++)
                {
                    if (rowArray[rowConter] == 1 || columnArray[columnCounter] == 1)
                    {
                        matrix[rowConter, columnCounter] = 0;
                    }
                }
            }

            //Print output 
            Console.WriteLine("After");
            Print2DMatrix(matrix);
            Console.WriteLine("------------------------------------------------------"); 

        }

Program For Creating the Matrix 

        public static int[,] CreateTestMatrix(int row, int column)
        {
            int[,] matrix = new int[row, column];
            int i, j;
            Random rnd = new Random();
            for (i = 0; i < row; i++)
            {
                //create a test matrix
                for (j = 0; j < column; j++)
                {
                    matrix[i, j] = rnd.Next(0, row * column);
                }
            }
            return matrix;
        }

Program for Printing the Matrix

        private static void Print2DMatrix(int[,] matrix)
        {
            for (int rowConter = 0; rowConter < matrix.GetLength(0); rowConter++)
            {
                {
                    for (int columnCounter = 0; columnCounter < matrix.GetLength(1); 
                                     columnCounter++)
                    {
                        Console.Write(matrix[rowConter, columnCounter] + " ");
                    }
                    Console.WriteLine(Environment.NewLine);
                }
            }
        }

Test

Today We will write a program for converting matrix’s row and columns to zero if any one element is zero.

Example

Code

        public static void RowColumnZero(int[,] matrix)
        {
            Console.WriteLine("------------------------------------------------------");
            Console.WriteLine("Before");
            Print2DMatrix(matrix);
            int rowConter;
            int columnCounter;

            rowConter = columnCounter = 0;
            int[] rowArray = new int[matrix.GetLength(0)];
            int[] columnArray = new int[matrix.GetLength(1)];

            for (rowConter = 0; rowConter < rowArray.Length; rowConter++)
            {

                for (columnCounter = 0; columnCounter < columnArray.Length; 
                                                        columnCounter++)
                {
                    if (matrix[rowConter, columnCounter] == 0)
                    {
                        rowArray[rowConter] = 1;
                        columnArray[columnCounter] = 1;
                    }
                }
            }


            for (rowConter = 0; rowConter < rowArray.Length; rowConter++)
            {
                for (columnCounter = 0; columnCounter < columnArray.Length; 
                                        columnCounter++)
                {
                    if (rowArray[rowConter] == 1 || columnArray[columnCounter] == 1)
                    {
                        matrix[rowConter, columnCounter] = 0;
                    }
                }
            }

            //Print output 
            Console.WriteLine("After");
            Print2DMatrix(matrix);
            Console.WriteLine("------------------------------------------------------"); 

        }

Program For Creating the Matrix 

        public static int[,] CreateTestMatrix(int row, int column)
        {
            int[,] matrix = new int[row, column];
            int i, j;
            Random rnd = new Random();
            for (i = 0; i < row; i++)
            {
                //create a test matrix
                for (j = 0; j < column; j++)
                {
                    matrix[i, j] = rnd.Next(0, row * column);
                }
            }
            return matrix;
        }

Program for Printing the Matrix

        private static void Print2DMatrix(int[,] matrix)
        {
            for (int rowConter = 0; rowConter < matrix.GetLength(0); rowConter++)
            {
                {
                    for (int columnCounter = 0; columnCounter < matrix.GetLength(1); 
                                     columnCounter++)
                    {
                        Console.Write(matrix[rowConter, columnCounter] + " ");
                    }
                    Console.WriteLine(Environment.NewLine);
                }
            }
        }

Test