1 package iYou.neugle.sort;
2
3 public class Merge_sort {
4
5 public static void MergeSort(double[] array, int start, int end) {
6 if (start < end) {
7 int middle = (start + end) / 2;
8 MergeSort(array, start, middle);
9 MergeSort(array, middle + 1, end);
10 Merge(array, start, middle, end);
11 }
12 }
13
14 private static void Merge(double[] array, int start, int middle, int end) {
15 int n1 = middle - start + 1;
16 int n2 = end - middle;
17 double[] L = new double[n1];
18 double[] R = new double[n2];
19 for (int i = 0; i < n1; i++) {
20 L[i] = array[start + i];
21 }
22 for (int i = 0; i < n2; i++) {
23 R[i] = array[middle + i + 1];
24 }
25 for (int i = 0, j = 0, k = start; k <= end; k++) {
26 if (j == n2 || (i < n1 && L[i] <= R[j])) {
27 array[k] = L[i];
28 i++;
29 } else {
30 array[k] = R[j];
31 j++;
32 }
33 }
34 }
35 }
