Reading 2 and 3 dimensional arrays from external file. Help please

Hello, I am trying to write a program that calculates the determinant of a 3*3 matrix using the Laplace expansion (if you dont know what this is it doesnt matter, you might still be able to help)

In an external file, say "elements.dat" i have 9 numbers, which are the elements of the matrix

eg:

1 2 3

4 5 6

7 8 9

I need to input these into the program, and evaluate the determinant using the laplace expansion - for this, I need to use an external function to calculate the determinant of the "minor" matricies (i.e the 2*2 matricies found by removing the ith row and jth column), by taking a 2 dimensional array as an input.

In particular, i need help in this last part, I have no idea how to get the program to make 2-dimensional arrays from the file "elements.dat"

Thanks! Sorry if this is confusing, im not too confident with programming, but i can try to clarify if needed.