include <iostream>

using namespace std;

class set
{
private:
    const unsigned int size; //rozmiar tablicy
    unsigned int i; //iterator
    int *elements; //tablica elementow
public:
    set(); // domyslny
    set(int); // tworzacy
    set(set const &); // kopiujacy
    int add(int);
    int del(int);
    ~set();

    set friend operator+(set const&, set const&);
    set friend operator-(set const&, set const&);
    set friend operator*(set const&, set const&);

};

set::set() :size(0), i(0)
{
    elements = new int [size]; //pusty zbior
}

set::set(int elem) :size(elem), i(0)
{
    elements = new int[size]; //tworzenie zbioru
}

set::set(set const &toCopy):size(toCopy.size),i(toCopy.i)
{
    elements = new int[size];
    for (int i = 0; i < toCopy.size; i++)
    {
        elements[i] = toCopy.elements[i];
    }
}

set::~set()
{
    delete[] elements;
    elements = NULL;
}

int set::add(int elem) //zwraca -1 jesli przekraczamy rozmiar tablicy
{
    if (size == i) return -1; //nie dodajemy wiecej niz w rozmiarze

    for (int j = 0; j < size; j++)
    {
        if (elements[j] == elem) return 0;
    }

    elements[i] = elem;
    i++;

    return 1;
}

int set::del(int element) //zwraca 0 gdy operacja sie uda
{
    int pos = 0; //iterator

    for (pos; pos < i; pos++)
    {
        if (element == elements[pos]) break;
        return 1;
    }
    while (pos <= i)
    {
        elements[pos] = elements[pos + 1];
        pos++;
    }
    i--;
    return 0;
}

set operator+(set const &first, set const &second)
{
    set newSet(first.i + second.i -1); //tworzymy nowy zbior

    for(int j=0; j<first.i; j++)
    {
        newSet.add(first.elements[j]);
    }
    for (int j = 0; j < second.i; j++)
    {
        newSet.add(second.elements[j]);
    }
    return newSet;
}

set operator-(set const &first, set const &second)
{

    int common[100]; //tablica elementow roznicy
    int sizeOfCommon = 0;
    bool match = 0; //jesli match == 1, element zostal znaleziony w drugiej tablicy i nie bedzie wpisany
    for (int i = 0; i < first.i; i++)
    {
        for (int j = 0; j < second.i; j++)
        {
            if (first.elements[i] == second.elements[j]) match = 1;
        }
        if (match == 0)
        {
            common[sizeOfCommon] = first.elements[i];
            sizeOfCommon++;
        }
        match = 0;
    }

    set newSet(sizeOfCommon);

    for (int i = 0; i < sizeOfCommon; i++)
    {
        newSet.elements[i] = common[i];
        newSet.i++;
    }
    return newSet;
}

set operator*(set const &first, set const &second)
{
    int common[100]; //tablica elementow wspolnych
    int sizeOfCommon = 0;
    for (int i = 0; i < first.i; i++)
    {
        for (int j = 0; j < second.i; j++)
        {
            if (first.elements[i] == second.elements[j])
            {
                common[sizeOfCommon] = second.elements[j];
                sizeOfCommon++;
            }
        }
    }
    set newSet(sizeOfCommon);
    for (int i = 0; i < sizeOfCommon; i++)
    {
        newSet.elements[i] = common[i];
        newSet.i++;
    }
    return newSet;
}

int main()
{
    set test(5);
    set test2(8);

    test.add(2);
    test.add(50);
    test.add(4);

    test2.add(2);
    test2.add(30);
    test2.add(60);

    set sumaZbiorow = test + test2;
    set roznica = test - test2;
    set wspolny = test * test2;

    test.del(50);

    return 0;