4.5

static void Main(string[] args)
        {
            int a = 10, b = 15, c = 0;
            SomeMul(a, b, c);
            char[] map = new char[15];
            map[2] = 'T';
            GenerateMap(map);
            Console.WriteLine(c);
            Console.WriteLine(map[2]);
        }
        static void SomeMul(int a, int b, int c)
        {
            c = a * b;
        }
        static void GenerateMap(char[] map)
        {
            for(int i = 0; i < map.Length; i++)
            {
                map[i] = 'P';
            }
        }