/*license*\
XBN-Java Library
Copyright (c) 2014, Jeff Epstein (aliteralmind __DASH__ github __AT__ yahoo __DOT__ com)
This software is dual-licensed under the:
- Lesser General Public License (LGPL) version 3.0 or, at your option, any later version;
- Apache Software License (ASL) version 2.0.
Either license may be applied at your discretion. More information may be found at
- http://en.wikipedia.org/wiki/Multi-licensing.
The text of both licenses is available in the root directory of this project, under the names "LICENSE_lgpl-3.0.txt" and "LICENSE_asl-2.0.txt". The latest copies may be downloaded at:
- LGPL 3.0: https://www.gnu.org/licenses/lgpl-3.0.txt
- ASL 2.0: http://www.apache.org/licenses/LICENSE-2.0.txt
\*license*/
package com.github.xbn.examples.util.non_xbn;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;
/**
<p>Sorts the <i>first</i> array in a two-dimensional array, and moves all partner elements (in the same "column") in the <i>second</i> to the same sort-destination index.</p>
<p>This was used as an answer to
<br/> <code><a href="http://stackoverflow.com/questions/22418151/sorting-2d-array-but-keeping-column-elements-together">http://stackoverflow.com/questions/22418151/sorting-2d-array-but-keeping-column-elements-together</a></code></p>
<p>{@code java SortOneArrayKeepSecondArrayElementsAligned}</p>
* @since 0.1.0
* @author Copyright (C) 2014, Jeff Epstein ({@code aliteralmind __DASH__ github __AT__ yahoo __DOT__ com}), dual-licensed under the LGPL (version 3.0 or later) or the ASL (version 2.0). See source code for details. <a href="http://xbnjava.aliteralmind.com">{@code http://xbnjava.aliteralmind.com}</a>, <a href="https://github.com/aliteralmind/xbnjava">{@code https://github.com/aliteralmind/xbnjava}</a>
**/
public class SortOneArrayKeepSecondArrayElementsAligned {
public static final void main(String[] ignored) {
int[][] intArrayArray = new int[][]{
{ 6, 3, 1, 2, 3, 0},
{ 2, 1, 6, 6, 2, 4}};
output2DArray("Unsorted", intArrayArray);
Map<Integer,List<TwoInts>> twoIntMap = new TreeMap<Integer,List<TwoInts>>();
for(int i = 0; i < intArrayArray[0].length; i++) {
int intIn0 = intArrayArray[0][i];
if(!twoIntMap.containsKey(intIn0)) {
List<TwoInts> twoIntList = new ArrayList<TwoInts>(intArrayArray.length);
twoIntList.add(new TwoInts(intArrayArray[0][i], intArrayArray[1][i]));
twoIntMap.put(intIn0, twoIntList);
} else {
twoIntMap.get(intIn0).add(new TwoInts(intArrayArray[0][i], intArrayArray[1][i]));
}
}
int idx = 0;
Iterator<Integer> itr2i = twoIntMap.keySet().iterator();
while(itr2i.hasNext()) {
List<TwoInts> twoIntList = twoIntMap.get(itr2i.next());
for(TwoInts twoi : twoIntList) {
intArrayArray[0][idx] = twoi.aElement;
intArrayArray[1][idx++] = twoi.bElement;
}
}
output2DArray("Sorted", intArrayArray);
}
private static final void output2DArray(String description, int[][] twoD_array) {
System.out.println(description + ":");
System.out.println("0: " + Arrays.toString(twoD_array[0]));
System.out.println("1: " + Arrays.toString(twoD_array[1]));
System.out.println();
}
}
class TwoInts {
public final int aElement;
public final int bElement;
public TwoInts(int a_element, int b_element) {
aElement = a_element;
bElement = b_element;
}
}