MergeSort - Recursiv

#include < iostream >
using namespace std;

void merge(int arr[], int l, int m, int r) {
    int i = l;
    int j = m + 1;
    int k = l;

    /* create temp array */
    int temp[5];

    while (i <= m && j <= r) {
        if (arr[i] <= arr[j]) {
            temp[k] = arr[i];
            i++;
            k++;
        }
        else {
            temp[k] = arr[j];
            j++;
            k++;
        }

    }

    /* Copy the remaining elements of first half, if there are any */
    while (i <= m) {
        temp[k] = arr[i];
        i++;
        k++;

    }

    /* Copy the remaining elements of second half, if there are any */
    while (j <= r) {
        temp[k] = arr[j];
        j++;
        k++;
    }

    /* Copy the temp array to original array */
    for (int p = l; p <= r; p++) {
        arr[p] = temp[p];
    }
}

/* l is for left index and r is right index of the
   sub-array of arr to be sorted */
void mergeSort(int arr[], int l, int r) {
    if (l < r) {
        // find midpoint
        int m = (l + r) / 2;

        // recurcive mergesort first and second halves
        mergeSort(arr, l, m);
        mergeSort(arr, m + 1, r);

        // merge
        merge(arr, l, m, r);
    }
}

int main() {
    int myarray[5];
    //int arr_size = sizeof(myarray)/sizeof(myarray[0]);
    int arr_size = 5;

    cout << "Enter 5 integers in any order: " << endl;
    for (int i = 0; i < 5; i++) {
        cin >> myarray[i];
    }
    cout << "Before Sorting" << endl;
    for (int i = 0; i < 5; i++) {
        cout << myarray[i] << " ";
    }
    cout << endl;
    mergeSort(myarray, 0, (arr_size - 1)); // mergesort(arr,left,right) called

    cout << "After Sorting" << endl;
    for (int i = 0; i < 5; i++) {
        cout << myarray[i] << " ";
    }

    return 0;
}