Method UnionFind

cpp/Graphs/connect_the_dots.cpp:10–16

    std::vector<int> parent;
    std::vector<int> size;
    UnionFind(int size) {
        parent.resize(size);
        this->size.resize(size, 1);
        for (int i = 0; i < size; i++) {
            parent[i] = i;
        }
    }
    
    bool unionSets(int x, int y) {
        int repX = findSet(x);