Question

I have a matrix (5×5) with values in them for example:

Matrix (1,1) Value: ‘a’

Matrix (1, 2) Value: ‘b’

Matrix (2, 1) Value: ‘c’

how would I be able to find the letter ‘a’ in that matrix and have it output the coordinates?

ie

user inputs ‘b’

[searches for ‘b’ in table]

output (1,2)

thanks in advance

Answer 1

It’s as simple as:

For i As Integer = 0 To LengthOfMatrix - 1
  For y As Integer = 0 To HeightOfMatrix - 1
    If Matrix(i, y) = "a" Then Console.Write(i & " " & y & vbCrLf)
  Next
Next

Asuming that you declared Matrix as:

Dim Matrix As Char(,) = {{"a", "b", "c", "d", "e"}, {"a", "b", "c", "d", "e"}, {"a", "b", "c", "d", "e"}, {"a", "b", "c", "d", "e"}, {"a", "b", "c", "d", "e"}}

And LengthOfMatrix And HeightOfMatrix should be the dimentions of your matrix. They could be switched to something more dynamic like:

For i As Integer = 0 To Matrix.GetLength(0) - 1 'Get's the length of the first dimension
  For y As Integer = 0 To Matrix.GetLength(1) - 1 'Get's the length of the second dimension
    If Matrix(i, y) = "a" Then Console.Write(i & " " & y & vbCrLf)
  Next
Next

In a short description, all that this loop does is it goes through all of the elements of the matrix and outputs the coordinates of every element that matches a certain criteria (In this case – equals to ‘a’).

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Note: In most programming languages array’s indexes begin from 0, so the first element in your matrix will be at coords (0,0).