2-dimensional array, merge sort

Question

I tried to sort the array, but I need to sort by merge sort, but it doesn't work correctly.

Please can anyone help me with that?

before I don't see any examples for merge-sort with a 2-dimensional array in turbo c++, so it is hard for me.

    #include<iostream.h>

    #include<conio.h>

    #include<stdlib.h>

    #include<stdio.h>

    void swap(int * a, int * b) {
        int buf = * a;
        * a = * b;
        * b = buf;
    }
    int partition(int ** A, int l, int r, int c) {
        int i;
        int * pivot_val = A[l / c, l % c];
        swap(A[l / c, l % c], A[r / c, r % c]);
        int j = l;
        for (i = l; i < r; i++) {
            if (A[i / c, i % c] <= pivot_val) {
                swap(A[i / c, i % c], A[j / c, j % c]);
                j++;
            }
        }
        swap(A[j / c, j % c], A[r / c, r % c]);
        return j;
    }
    void quicksort_r(int ** A, int l, int r, int c) {
        if (l < r) {
            int pivot = partition(A, l, r, c);
            quicksort_r(A, l, pivot - 1, c);
            quicksort_r(A, pivot + 1, r, c);
        }
    }
    void quicksort(int ** A, int rows, int columns) {
        quicksort_r(A, 0, rows * columns - 1, columns);
    }
    void main() {
        int rows, columns;
        int i, j;
        clrscr();
        cout << "Write count of rows: ";
        cin >> rows;
        cout << "Write count of columns: ";
        cin >> columns;
        int ** A = new int[rows, columns];
        randomize();
        for (j = 0; j < columns; j++) {
            for (i = 0; i < rows; i++) {
                A[rows, columns] = random(100);
                cout << "A[" << i << "][" << j << "] = " << A[rows, columns] << "\n";
            }
        }
        quicksort( * A, rows, columns);
        getch();
    }