unió és metszet

        #region 6. feladat

        static void feladat6()
        {
            Console.Clear();
            feladat6_kiírás();
            Console.ReadLine();
        }
        static void unio(int[] a, int[] b, int[] c)
        {
            for (int i = 0; i < a.Length; i++)
            {
                c[i] = a[i];
            }
            for (int i = 0; i < b.Length; i++)
            {
                bool van = false;
                for (int j=0;j<c.Length;j++)
                {
                    if (b[i] == c[j]) van = true;
                }
                if (van == false) c[a.Length + i] = b[i];
            }
        }

        static void feladat6_kiírás()
        {
            int[] a = new int[3];
            int[] b = new int[3];
            int[] c = new int[a.Length + b.Length];
            for (int i = 0; i < a.Length; i++) a[i] = int.Parse(Console.ReadLine());
            for (int i = 0; i < b.Length; i++) b[i] = int.Parse(Console.ReadLine());
            for (int i = 0; i < c.Length; i++) c[i] = ' ';
            unio(a, b, c);

            Console.Clear();
            Console.Write("1, halmaz: "); for (int i = 0; i < a.Length; i++) Console.Write("{0} ", a[i]);
            Console.WriteLine();
            Console.Write("2, halmaz: "); for (int i = 0; i < b.Length; i++) Console.Write("{0} ", b[i]);
            Console.WriteLine();
            Console.Write("Unió: "); for (int i = 0; i < c.Length; i++) if (c[i] != ' ') Console.Write("{0} ", c[i]);
        }

        #endregion

        #region 7. feladat

        static void feladat7() // metszet
        {
            Console.Clear();
            feladat7_kiírás();
            Console.ReadLine();
        }

        static void metszet(int[] a, int[] b, int[] c)
        {

            for (int i = 0; i < a.Length; i++)
            {
                bool van = false;
                for (int j=0;j<b.Length;j++)
                {
                    if (a[i] == b[j]) van = true;
                }
                if (van) c[i] = a[i];
            }
        }
        static void feladat7_kiírás()
        {
            int nagyobb;
            int[] a = new int[5];
            int[] b = new int[3];
            if (a.Length > b.Length) nagyobb = a.Length; else nagyobb = b.Length;
            int[] c = new int[nagyobb];
            for (int i = 0; i < a.Length; i++) a[i] = int.Parse(Console.ReadLine());
            for (int i = 0; i < b.Length; i++) b[i] = int.Parse(Console.ReadLine());
            for (int i = 0; i < c.Length; i++) c[i] = ' ';
            metszet(a, b, c);

            Console.Clear();
            Console.Write("1, halmaz: "); for (int i = 0; i < a.Length; i++) Console.Write("{0} ", a[i]);
            Console.WriteLine();
            Console.Write("2, halmaz: "); for (int i = 0; i < b.Length; i++) Console.Write("{0} ", b[i]);
            Console.WriteLine();
            Console.Write("Metszet: "); for (int i = 0; i < c.Length; i++) if (c[i] != ' ') Console.Write("{0} ", c[i]);
        }

        #endregion