Mergesort void MergeSort(int[] arr, int left, int right) { if (left < right) { int mid = (left + right) / 2; MergeSort(arr, left, mid); MergeSort(arr, mid + 1, right); Follow on: Merge(arr, left, mid, right); } } void Merge(int[] arr, int left, int mid, int right) { int n1 = mid - left + 1; int n2 = right - mid; int[] L = new int[n1]; int[] R = new int[n2];
rray.Copy(arr, left, L, 0, n1);
rray.Copy(arr, mid + 1, R, 0, n2);
int i = 0, j = 0, k = left;while (i < n1 && j < n2)
rr[k++] = (L[i] <= R[j]) ? L[i++] : R[j++];
while (i < n1) arr[k++] = L[i++];
while (j < n2) arr[k++] = R[j++];
}Explanation:
Divide array, sort left & right halves, then merge sorted halves.