SDA - test 6 - 2021-2022 - Преброяване на области

#include <iostream>
#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <unordered_map>
#include <set>

using namespace std;

struct UnionFind {
    vector<int> parents;
public:
    UnionFind(int count) : parents(count) {
        for (int i = 0; i < count; i++)
        {
            parents[i] = i;
        }
    }
    bool areInOneSet(int a, int b) {
        return getParent(a) == getParent(b);
    }

    int getParent(int idx) {
        if (parents[idx] == idx)
        {
            return idx;
        }

        return parents[idx] = getParent(parents[idx]);
    }

    void unite(int a, int b) {
        parents[getParent(a)] = getParent(b);
    }

    int countUniqueParents() {
        set<int> unique;

        for (size_t i = 0; i < parents.size(); i++)
        {
            unique.insert(parents[i] = getParent(i));
        }
        return unique.size();
    }
};

int main()
{
    int t, x, y, a, b;

    cin >> t;

    vector<int> results;

    for (size_t i = 0; i < t; i++)
    {
        cin >> x >> y;
        UnionFind graph(x);
        for (size_t j = 0; j < y; j++)
        {
            cin >> a >> b;
            graph.unite(a, b);
        }
        results.push_back(graph.countUniqueParents());
    }

    for (auto num : results) {
        cout << num << " ";
    }
}