In class we are currently making lottery tickets as a project, I'm currently stuck on a question with equals: The same rows are not allowed to appear multiple times on the same ticket.

I have tried a couple of things, but nothing has been working yet.

public class TalRækker //rows
{
    static Random rnd = new Random();
    public static int[,] Line()
    {
        int[,] line = new int[10, 7];
        //int x = rnd.Next(1, 36);

        for (int i = 0; i < line.GetLength(0); i  )
        {
            for (int j = 0; j < line.GetLength(1); j  )
            {
                line[i, j] = rnd.Next(1, 36);
            }
        }
        return line;


    }
    public static void Print2DArray<T>(T[,] line)
    {
        var lineNumber = 1;
        for (int i = 0; i < line.GetLength(0); i  )
        {
            Console.Write(" {0:D2}.\t", lineNumber);
            for(int j = 0; j < line.GetLength(1); j  )
            {
                Console.Write("{0:D2} ", line[i, j]);
            }
            Console.WriteLine();
            lineNumber  ;
        }
    }

CodePudding user response：

I would be tempted to use a jagged array to make this a little easier to handle. I'd then split the functionality required into separate methods to allow recursion if there are duplicates:

    static Random rnd = new Random();
    public static int[][] GenerateTicket(int numberOfRows, int rowLength)
    {
        var lines = new int[numberOfRows][];

        for (int i =0; i < lines.Length; i  )
        {
            lines[i] = GenerateLine(rowLength, lines);
        }

        return lines;
    }

    public static int[] GenerateLine(int rowLength, int[][] existingLines)
    {
        var newLine = new int[rowLength];
        for (int j = 0; j < rowLength; j  )
        {
            newLine[j] = GenerateNumber(newLine);
        }

        var orderedLine = newLine.OrderBy(n => n).ToArray();
        var exists = existingLines.Where(line => line != null).Any(line => line.SequenceEqual(orderedLine));

        // If a line already exists, call the method again to generate a new line, otherwise return the line.
        return exists ? GenerateLine(rowLength, existingLines) : orderedLine;
    }

    public static int GenerateNumber(int[] line)
    {
        var number = rnd.Next(1, 36);
        // Check if the line already contains the number, if so, call the method again to generate a new number, otherwise return the number.
        return line.Contains(number) ? GenerateNumber(line) : number;
    }

    public static void Print2DArray<T>(T[][] lines)
    {
        var lineNumber = 1;
        for (int i=0; i < lines.Length; i  )
        {
            Console.Write(" {0:D2}.\t", lineNumber);
            lineNumber  ;
            for (int j = 0; j < lines[i].Length; j  )
            {
                Console.Write("{0:D2} ", lines[i][j]);
            }
            Console.WriteLine();
        }
    }

Update

I've sorted the newLine before using SequenceEqual, so that this will compare previously ordered lines with this and therefore return true/false correctly.

CodePudding user response：

I assume that this is an array exercise. Otherwise I would prefer to use a List.

So you could do something similar to the following. Please note how each function follows the single responsibility principle and usage of access modifiers.

It is a good use case here for Do-While loop as your condition depends on the first outcome of row generation.

I did not check the occurrence of the same number in a row as you did not state that in your question.

public class TalRækker
{
    static Random rnd = new Random();
    public static int[,] GenerateLotteryTicket(int totalLines, int lineLength)
    {
        
        int[,] lines = new int[totalLines, lineLength];
        int[] newLine = new int[lineLength];


        for (int i = 0; i < totalLines; i  )
        {
            do
            {
                newLine = GenerateLine(lineLength);
            }
            while (ExistInTicket(lines,newLine));

            for (int j = 0; j < lineLength; j  )
            {
                lines[i,j] = newLine[j];
            }
        }
        return lines;
    }

    private static int[] GenerateLine(int lineLength)
    {
        int[] row = new int[lineLength];
        for (int i = 0; i < lineLength; i  )
        {
            row[i] = rnd.Next(1, 36);
        }
        return row;
    }
    private static bool ExistInTicket(int[,] ticket, int[] line)
    {
        bool rowMatchFound;
        for(int i = 0; i < ticket.GetLength(0); i  )
        {
            rowMatchFound = true;
            for (int j = 0; j < ticket.GetLength(1); j  )
            {
                if(ticket[i,j] != line[j])
                {
                    rowMatchFound = false;
                    break;
                }
            }
            if(rowMatchFound) return true;
        }
        return false;
    }

    public static void Print2DArray<T>(T[,] line)
    {
        var lineNumber = 1;
        for (int i = 0; i < line.GetLength(0); i  )
        {
            Console.Write(" {0:D2}.\t", lineNumber);
            for (int j = 0; j < line.GetLength(1); j  )
            {
                Console.Write("{0:D2} ", line[i, j]);
            }
            Console.WriteLine();
            lineNumber  ;
        }
    }
}