下面代码实现了归并排序。下述关于归并排序的说法中，不正确的是（ ）。
void merge(vector<int>& arr, vector<int>& temp, int l, int mid, int r) { int i = l, j = mid + 1, k = l; while (i <= mid && j <= r) { if (arr[i] <= arr[j]) temp[k++] = arr[i++]; else temp[k++] = arr[j++]; } while (i <= mid) temp[k++] = arr[i++]; while (j <= r) temp[k++] = arr[j++]; for (int p = l; p <= r; p++) arr[p] = temp[p];} void mergeSort(vector<int>& arr, vector<int>& temp, int l, int r) { if (l >= r) return; int mid = l + (r - l) / 2; mergeSort(arr, temp, l, mid); mergeSort(arr, temp, mid + 1, r); merge(arr, temp, l, mid, r);}