aparler/RosettaCodeData
1
0
Fork 0
Code Issues 12 Pull requests 3 Projects Releases Packages Wiki Activity Actions

Data update

Browse source
This commit is contained in:
Ingy döt Net 2024-10-16 18:07:41 -07:00
parent 81fd053722
commit 52a6ef48dd
10248 changed files with 63654 additions and 6775 deletions
Download patch file Download diff file Expand all files Collapse all files

29
Task/Combinations/Java/combinations-2.java Normal file
View file

@ -0,0 +1,29 @@
import java.util.ArrayList;
import java.util.List;
public final class Combinations {
public static void main(String[] args) {
System.out.println(createCombinations(List.of( 0, 1, 2, 3, 4 ), 3));
System.out.println(createCombinations(List.of( "Crosby", "Nash", "Stills", "Young" ), 3));
}
private static <T> List<List<T>> createCombinations(List<T> elements, int k) {
List<List<T>> combinations = new ArrayList<List<T>>();
createCombinations(elements, k, new ArrayList<T>(), combinations, 0);
return combinations;
}
private static <T> void createCombinations(
List<T> elements, int k, List<T> accumulator, List<List<T>> combinations, int index) {
if ( accumulator.size() == k ) {
combinations.addFirst( new ArrayList<T>(accumulator) );
} else if ( k - accumulator.size() <= elements.size() - index ) {
createCombinations(elements, k, accumulator, combinations, index + 1);
accumulator.add(elements.get(index));
createCombinations(elements, k, accumulator, combinations, index + 1);
accumulator.removeLast();
}
}
}