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package ee.ttu.algoritmid.bond;

import java.util.HashMap;
import java.util.Map;
import java.util.Objects;

public class DisjointSubsets {

    private Map<String, String> hashMap = new HashMap<>();
    public String find(String element) throws IllegalArgumentException {

        if (Objects.equals(hashMap.get(element), element)) {
            return element;
        }
        // should throw IllegalArgumentException if any of elements is not present
        if (!hashMap.containsKey(element)) throw new IllegalArgumentException();

        return find(hashMap.get(element));
    }
    public void union(String element1, String element2) throws IllegalArgumentException {
        // should throw IllegalArgumentException if any of elements is not present
        var a = find(element1);
        if (a == null) throw  new IllegalArgumentException();
        var b = find(element2);
        if (b == null) throw  new IllegalArgumentException();

        hashMap.put(a, b);
    }

    public void addSubset(String element) throws IllegalArgumentException {
        // should throw IllegalArgumentException if any of elements is not present
        if (hashMap.containsKey(element)) throw new IllegalArgumentException();

        hashMap.put(element, element);
    }
}