merge_sort

#include <iostream>
using namespace std;

int min(int a, int b)
{
    return (a < b ? a : b);
}

int* cpy(int* B, int* Arr, int left, int right, int& k)
{
    for(int i = left; i <= right; i++)
    {
        B[k] = Arr[i];
        k++;
    }
    return B;
}

void MergeSort(int*& Arr, int n, int deg)
{
    int* B = new int[n];
    int i = 0;
    int j = deg;
    int k = 0;
    int p = j;
    int q = min(n - j, p);
    int l = 0;
    int r = 0;


    while (j < n)
    {
        l = r + p;
        r = l + q;
        while (i < l && j < r)
        {
            if (Arr[i] < Arr[j])
            {
                B[k] = Arr[i];
                i++;
            }
            else
            {
                B[k] = Arr[j];
                j++;
            }
            k++;
        }
        if (i == l)
            B = cpy(B, Arr, j, r - 1, k);
        else
            B = cpy(B, Arr, i, l - 1, k);
        i = r;
        j = r + p;
        q = min(n - j, p);
    }

    if (i < n)
        B = cpy(B, Arr, i, n - 1, k);

    for (int i = 0; i < n; i++)
        Arr[i] = B[i];
    delete[]B;
}

int* Merge(int* Arr, int n, int size)
{
    for (int i = n; i < size; i += n)
        MergeSort(Arr, size, i);
    return Arr;
}

int main()
{
    int k, n;
    cin >> k >> n;

    int** arr = new int*[k];
    for (int i = 0; i < k; i++)
        arr[i] = new int[n];
    for (int i = 0; i < k; i++)
        for (int j = 0; j < n; j++)
            cin >> arr[i][j];

    int* B = new int[n*k];
    int s = 0;

    for (int i = 0; i < k; i++)
        for (int j = 0; j < n; j++)
        {
            B[s] = arr[i][j];
            s++;
        }

    for (int i = 0; i < n*k; i++)
        cout << B[i] << ' ';
    cout << endl;

    B = Merge(B, n, n*k);
    for (int i = 0; i < n*k; i++)
        cout << B[i] << ' ';
    return 0;
}