annotate src/org/tmatesoft/hg/internal/ArrayHelper.java @ 485:cdd53e5884ae

Do not add anything to exception message in case no details are known
author Artem Tikhomirov <tikhomirov.artem@gmail.com>
date Thu, 09 Aug 2012 15:45:18 +0200
parents b9592e21176a
children 6334b0267103
rev   line source
307
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
1 /*
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
2 * Copyright (c) 2011 TMate Software Ltd
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
3 *
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
4 * This program is free software; you can redistribute it and/or modify
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
5 * it under the terms of the GNU General Public License as published by
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
6 * the Free Software Foundation; version 2 of the License.
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
7 *
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
8 * This program is distributed in the hope that it will be useful,
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
11 * GNU General Public License for more details.
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
12 *
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
13 * For information on how to redistribute this software under
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
14 * the terms of a license other than GNU General Public License
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
15 * contact TMate Software at support@hg4j.com
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
16 */
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
17 package org.tmatesoft.hg.internal;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
18
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
19 /**
311
b9592e21176a Tests for array sort and reverse index building helper
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 310
diff changeset
20 * Internal alternative to Arrays.sort to build reversed index along with sorting
307
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
21 *
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
22 * @author Artem Tikhomirov
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
23 * @author TMate Software Ltd.
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
24 */
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
25 public class ArrayHelper {
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
26 private int[] reverse;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
27
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
28 @SuppressWarnings("unchecked")
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
29 public void sort(Comparable<?>[] a) {
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
30 // Object[] aux = (Object[]) a.clone();
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
31 reverse = new int[a.length];
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
32 sort1((Comparable<Object>[])a, 0, a.length);
310
237de162be28 Fix building sort reverse array when element was initially in correct position.
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 307
diff changeset
33 for (int i = 0; i < reverse.length; i++) {
237de162be28 Fix building sort reverse array when element was initially in correct position.
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 307
diff changeset
34 // element that was not moved don't have an index in reverse.
237de162be28 Fix building sort reverse array when element was initially in correct position.
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 307
diff changeset
35 // perhaps, can do it inside sort alg?
311
b9592e21176a Tests for array sort and reverse index building helper
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 310
diff changeset
36 // Alternatively, may start with filling reverse[] array with initial indexes and
b9592e21176a Tests for array sort and reverse index building helper
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 310
diff changeset
37 // avoid != 0 comparisons in #swap altogether?
310
237de162be28 Fix building sort reverse array when element was initially in correct position.
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 307
diff changeset
38 if (reverse[i] == 0) {
237de162be28 Fix building sort reverse array when element was initially in correct position.
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 307
diff changeset
39 reverse[i] = i+1;
237de162be28 Fix building sort reverse array when element was initially in correct position.
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 307
diff changeset
40 }
237de162be28 Fix building sort reverse array when element was initially in correct position.
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 307
diff changeset
41 }
307
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
42 }
311
b9592e21176a Tests for array sort and reverse index building helper
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 310
diff changeset
43
b9592e21176a Tests for array sort and reverse index building helper
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 310
diff changeset
44 /**
b9592e21176a Tests for array sort and reverse index building helper
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 310
diff changeset
45 * Slightly modified version of Arrays.sort1(int[], int, int) quicksort alg (just to deal with Object[])
b9592e21176a Tests for array sort and reverse index building helper
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 310
diff changeset
46 */
307
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
47 private void sort1(Comparable<Object> x[], int off, int len) {
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
48 // Insertion sort on smallest arrays
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
49 if (len < 7) {
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
50 for (int i=off; i<len+off; i++)
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
51 for (int j=i; j>off && x[j-1].compareTo(x[j]) > 0; j--)
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
52 swap(x, j, j-1);
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
53 return;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
54 }
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
55
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
56 // Choose a partition element, v
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
57 int m = off + (len >> 1); // Small arrays, middle element
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
58 if (len > 7) {
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
59 int l = off;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
60 int n = off + len - 1;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
61 if (len > 40) { // Big arrays, pseudomedian of 9
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
62 int s = len/8;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
63 l = med3(x, l, l+s, l+2*s);
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
64 m = med3(x, m-s, m, m+s);
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
65 n = med3(x, n-2*s, n-s, n);
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
66 }
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
67 m = med3(x, l, m, n); // Mid-size, med of 3
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
68 }
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
69 Comparable<Object> v = x[m];
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
70
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
71 // Establish Invariant: v* (<v)* (>v)* v*
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
72 int a = off, b = a, c = off + len - 1, d = c;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
73 while(true) {
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
74 while (b <= c && x[b].compareTo(v) <= 0) {
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
75 if (x[b] == v)
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
76 swap(x, a++, b);
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
77 b++;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
78 }
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
79 while (c >= b && x[c].compareTo(v) >= 0) {
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
80 if (x[c] == v)
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
81 swap(x, c, d--);
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
82 c--;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
83 }
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
84 if (b > c)
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
85 break;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
86 swap(x, b++, c--);
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
87 }
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
88
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
89 // Swap partition elements back to middle
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
90 int s, n = off + len;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
91 s = Math.min(a-off, b-a ); vecswap(x, off, b-s, s);
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
92 s = Math.min(d-c, n-d-1); vecswap(x, b, n-s, s);
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
93
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
94 // Recursively sort non-partition-elements
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
95 if ((s = b-a) > 1)
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
96 sort1(x, off, s);
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
97 if ((s = d-c) > 1)
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
98 sort1(x, n-s, s);
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
99 }
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
100
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
101 /**
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
102 * Swaps x[a .. (a+n-1)] with x[b .. (b+n-1)].
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
103 */
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
104 private void vecswap(Object[] x, int a, int b, int n) {
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
105 for (int i=0; i<n; i++, a++, b++) {
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
106 swap(x, a, b);
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
107 }
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
108 }
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
109
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
110 /**
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
111 * Returns the index of the median of the three indexed integers.
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
112 */
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
113 private static int med3(Comparable<Object>[] x, int a, int b, int c) {
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
114 return (x[a].compareTo(x[b]) < 0 ?
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
115 (x[b].compareTo(x[c]) < 0 ? b : x[a].compareTo(x[c]) < 0 ? c : a) :
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
116 (x[b].compareTo(x[c]) > 0 ? b : x[a].compareTo(x[c]) > 0 ? c : a));
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
117 }
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
118
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
119
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
120 /**
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
121 * @return the reverse
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
122 */
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
123 public int[] getReverse() {
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
124 return reverse;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
125 }
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
126
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
127 /**
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
128 * Swaps x[a] with x[b].
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
129 */
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
130 private void swap(Object[] x, int a, int b) {
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
131 Object t = x[a];
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
132 x[a] = x[b];
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
133 x[b] = t;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
134 int z1 = reverse[a] != 0 ? reverse[a] : a+1;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
135 int z2 = reverse[b] != 0 ? reverse[b] : b+1;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
136 reverse[b] = z1;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
137 reverse[a] = z2;
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
138 }
2f2ab5c27f41 Collect sort reverse indexes along with array sorting
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
139 }