I have a 2D Array in C# with user input to fill the Array. I need help to find the sum for every column and row.

var input = Console.ReadLine();
        var n = int.Parse(input);

        int[,] intArr = new int[n, 3];

        for (int i = 0; i < n; i  )
        {
            input = Console.ReadLine();
            var parts = input.Split(' ');

            for (int j = 0; j < 3; j  )
            {
                intArr[i, j] = int.Parse(parts[j]);
            }
        }
        if (n == 1)
        {
            Console.WriteLine("Sum of column "   Convert.ToString(n)   ": "   (intArr[n - 1, 0]   intArr[n - 1, 1]   intArr[n - 1, 2]));
            Console.WriteLine("Row1: "   (intArr[n - 1, 0]));
            Console.WriteLine("Row2: "   (intArr[n - 1, 1]));
            Console.WriteLine("Row3: "   (intArr[n - 1, 2]));
        }
        if (n == 2)
        {
            Console.WriteLine("Sum of column "   Convert.ToString(n - 1)   ": "   (intArr[n - 2, 0]   intArr[n - 2, 1]   intArr[n - 2, 2]));
            Console.WriteLine("Sum of column "   Convert.ToString(n)   ": "   (intArr[n - 1, 0]   intArr[n - 1, 1]   intArr[n - 1, 2]));
            Console.WriteLine("Row 1: "   (intArr[n - 2, 0]   intArr[n - 1, 0]));
            Console.WriteLine("Row 2: "   (intArr[n - 2, 1]   intArr[n - 1, 1]));
            Console.WriteLine("Row 3: "   (intArr[n - 1, 2]   intArr[n - 1, 1]));

      }
   }
User input:
       2
       1 2 3
       4 5 6
       The output:  
       Sum of column 1: 6
       Sum of column 2: 15
       Row 1: 5
       Row 2: 7
       Row 3: 11

I want this output for N columns enter by user, but I am stuck! Thank you!

CodePudding user response：

Not sure, is your problem that you get an undesired result or that you have a model with a fixed number of elements? An array is a fixed size data container, so if you want any number of columns the architecture perhaps is where you want to change away from array. Anyway, problem 1 is that you let user chose how many rows they want, but now how many column, so presuming there will be 3 conflicts with you data. So you have on array the .getUpperBound() for that which takes a range parameter and this way we can use a dynamic strucure

//From:
for (int i = 0; i < n; i  )
{
        input = Console.ReadLine();
        var parts = input.Split(' ');

        for (int j = 0; j < 3; j  )
        {
            intArr[i, j] = int.Parse(parts[j]);
        }
    }

//TO:  
var rows = new List<int[]>();      
for (int i = 0; i < n; i  )
{
    input = Console.ReadLine();
    var parts = input.Split(' ');
    var listOf = new List<int>();                

    for (int j = 0; j < parts.GetUpperBound(0); j  )
        {
            listOf.Add(int.Parse(parts[j]));
        }
    rows.Add(listOf.ToArray());
}

from https://docs.microsoft.com/en-us/dotnet/api/system.linq.enumerable.aggregate?view=net-5.0 You get the aggregation capability

    [Fact]
    public void SumExerciseTest()
    {
    /*
     The output:  
     Sum of column 1: 6
     Sum of column 2: 15
     Row 1: 5
     Row 2: 7
     Row 3: 11 => 9
    */
        var testData = new[] { "1 2 3", "4 5 6" };

        var input = "2"; // Console.ReadLine();
        var n = int.Parse(input);

        var rows = new List<int[]>(n);

        for (int i = 0; i < n; i  )
        {
            input = testData[i];
            var parts = input.Split(' ');

            var listOf = new List<int>();
            for (int j = 0; j <= parts.GetUpperBound(0); j  )
            {
                listOf.Add(int.Parse(parts[j]));
            }
            rows.Add(listOf.ToArray());
        }

        var rowSums = new List<int>(n);
        foreach (int[] row in rows)
        {
            rowSums.Add(row.Aggregate((result, item) => result   item));
        }

        int maxLength = 0;
        var rowLengths = new List<int>(n);
        foreach (int[] row in rows)
        {
            rowLengths.Add(row.Length);
        }
        maxLength = rowLengths.Max();

        int[] columnSums = new int[maxLength];
        for (int idx = 0; idx < columnSums.Length; idx  ){
            foreach (var row in rows)
            {
                if (row.GetUpperBound(0) >= idx)
                {
                    columnSums[idx]  = row[idx];
                }
            }
        }

        int counter = 0;
        //Outputting:
        foreach(var sum in rowSums)
        {
            counter  = 1;
            System.Diagnostics.Debug.WriteLine($"Row {counter}: {sum}");
        }

        counter = 0;
        foreach(var sum in columnSums)
        {
            counter  = 1;
            System.Diagnostics.Debug.WriteLine($"Column {counter}: {sum}");
        }

CodePudding user response：

Well, let's implement (extract) methods for summing arbitrary column and row:

  private static int SumColumn(int[,] array, int column) {
    if (array == null)
      throw new ArgumentNullException(nameof(array));

    if (column < 0 || column >= array.GetLength(1))
      throw new ArgumentOutOfRangeException(nameof(column)); 

    int result = 0;

    for (int r = 0; r < array.GetLength(0);   r)
      result  = array[r, column];

    return result; 
  }

  private static int SumRow(int[,] array, int row) {
    if (array == null)
      throw new ArgumentNullException(nameof(array));

    if (row < 0 || row >= array.GetLength(0))
      throw new ArgumentOutOfRangeException(nameof(row)); 

    int result = 0;

    for (int c = 0; c < array.GetLength(1);   c)
      result  = array[row, c];

    return result; 
  }

then you can put

  for (int c = 0; c < intArr.GetLength(1);   c)
    Console.WriteLine($" Sum of column {c   1}: {SumColumn(intArr, c)}"); 

  for (int r = 0; r < intArr.GetLength(0);   r)
    Console.WriteLine($" Sum of row {r   1}: {SumRow(intArr, r)}");