Thread: hi i need help with the outputs for number combinations, I want to restrict the outputs to suits of 3 numbers

Hi i need help to refine the code below, I want to be able to
(A) Restrict the number of output values per line to 3 numbers,
(B) Remove Duplicate lines, where the same numbers are duplicated just outputted in a different order.
(C) Count the number of outlines
(D) Add a fixed column to the outputs that has an ascending count from 1 upwards

thanks a lot i'm very new to Coding and was able to come across this which aided in the concept of what i'm trying to achieve
the code is as follows:

package num.com.t1;
import java.util.*;
import java.util.concurrent.atomic.AtomicInteger;
/**
*
*
*/
public class NumComT1 {


public static void main(String... args) {
Bag<Integer> b = new Bag<>();
b.countFor(1, 1);
b.countFor(2, 1);
b.countFor(3, 1);
b.countFor(4, 1);
b.countFor(5, 1);
b.countFor(6, 1);
b.countFor(7, 1);
b.countFor(8, 1);

Set<String> set = new LinkedHashSet<>();
for (List<Integer> list : b.combinations()) {
System.out.println(list);
String s = list.toString();
if (!set.add(s))
System.err.println("Duplicate entry " + s);
}
}
}

class Bag<E> {
final Map<E, AtomicInteger> countMap = new LinkedHashMap<>();

void countFor(E e, int n) {
countMap.put(e, new AtomicInteger(n));
}

void decrement(E e) {
AtomicInteger ai = countMap.get(e);
if (ai.decrementAndGet() < 1)
countMap.remove(e);
}

void increment(E e) {
AtomicInteger ai = countMap.get(e);
if (ai == null)
countMap.put(e, new AtomicInteger(1));
else
ai.incrementAndGet();
}

List<List<E>> combinations() {
List<List<E>> ret = new ArrayList<>();
List<E> current = new ArrayList<>();
combinations0(ret, current);
return ret;
}

private void combinations0(List<List<E>> ret, List<E> current) {
if (countMap.isEmpty()) {
ret.add(new ArrayList<E>(current));
return;
}
int position = current.size();
current.add(null);
List<E> es = new ArrayList<>(countMap.keySet());
if (es.get(0) instanceof Comparable)
Collections.sort((List) es);
for (E e : es) {
current.set(position, e);
decrement(e);
combinations0(ret, current);
increment(e);
}
current.remove(position);
}
}

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