Printing contents of matrix by using pointer

Question

Here is my assignment: arrPrintMatrix(int *matrix, int m, int n): prints the content of the matrix[m][n] to the screen in table format.

And here is my code:

    #include <stdio.h>
    #include <malloc.h>

    int main() {

    void arrPrintMatrix(int *matrix, int m, int n);

    int matrix[2][3] = {{5, 10 , 15}, {0, 2, 4}};
    int *ptr;
    ptr = &matrix[0][0];
    arrPrintMatrix(ptr, 2, 3);

    return 0;
    }


    void arrPrintMatrix(int *matrix, int m, int n) {
    int i, j;

    for (i = 0; i < m; i++) {
        printf("\n");
        for (j = 0; j < n; j++) {
            printf("%d\t", matrix[i] + j);
        }
    }

    }

But when I run this code, I get 5 6 and 7 as first row, 10 11 and 12 as second row. So something wrong with matrix[i] + j. How should I fix this?

By the way, I'm so confused about arrays of pointers, malloc, pointers to functions, so generally I'm confused about pointers. I would be glad if you suggest some web pages or videos about that.

Answer 1

Change the line

        printf("%d\t", matrix[i] + j);

to

        printf("%d\t", matrix[i*n+j]);

Update

Layout of memory of 2D arrays is nicely explained in this article.

Answer 2

mChange:

 matrix[i] + j

To:

matrix[(i*n)+j]