#include <iostream>

#define SIZE 4

void printCombinationsWithRepetitions(int * arr, int * combs, int index,
	int sizeOfComb, int beg, int end)
{
	if (index == sizeOfComb)
	{
		for (int i = 0; i < index; ++i)
			std::cout << arr[combs[i]];

		std::cout << '\n';
		return;
	}

	for (int j = beg; j <= end; ++j)
	{
		combs[index] = j;
		printCombinationsWithRepetitions(arr, combs, index + 1, sizeOfComb, j, end);
	}
}

void combinationsWithRepetitions(int * arr, int size, int sizeOfComb)
{
	int * temp = new int[sizeOfComb + 1];
	printCombinationsWithRepetitions(arr, temp, 0, sizeOfComb, 0, size - 1);

	delete[] temp;
}

int main()
{
	int * arrayOfNumbers = new int[SIZE];
	for (int i = 0; i < SIZE; ++i)
		arrayOfNumbers[i] = i + 1;

	int sizeOfComb = 2;

	combinationsWithRepetitions(arrayOfNumbers, SIZE, sizeOfComb);

	delete[] arrayOfNumbers;
	return 0;
}