int** composition(int** a, int** b, int n)
{
	int** c = new int* [n];
	for (int i = 0; i < n; i++)
		c[i] = new int[n];
	for (int i = 0; i < n; i++)
	{
		for (int j = 0; j < n; j++)
		{
			c[i][j] = 0;
			for (int h = 0; h < n; h++)
				c[i][j] += a[i][h] * b[h][j];
		}
	}
	return c;
}