namespace ConsoleApplication1
{
    class Program
    {

        struct SubjectScore
        {
            public double lang;
            public double math;
            public double eng;
        }



        static void Main(string[] args)
        {





            Console.WriteLine("1부터 8번중에 선택해주십시오. 9번은 종료입니다");

            int i = Convert.ToInt32(Console.ReadLine());

            if (i == 1)
            {
                Console.WriteLine("안녕하세요");


            }


            else if (i == 2)
            {
                int myAge;
                string myName;

                myAge = 23;
                myName = "김태완";

                Console.WriteLine("나의 이름은 : " + myName);
                Console.WriteLine("나의 나이는 : " + myAge);
            }

            else if (i == 3)
            {
                int val1;
                int val2;
                int val3;

                val1 = 4;
                val2 = 5;
                val3 = val1 + val2;
                Console.WriteLine(val3);
                Console.WriteLine(val3++);
                Console.WriteLine(val3);
                Console.WriteLine(++val3);
                Console.WriteLine(val3);
            }
            else if (i == 4)
            {
                int val1;
                Console.WriteLine("정수를 입력하세요!");
                val1 = Convert.ToInt32(Console.ReadLine());
                if (val1 % 2 == 0)
                {
                    Console.WriteLine(val1 + "은 짝수 입니다.");
                }
                else
                {
                    Console.WriteLine(val1 + "은 홀수 입니다.");
                }

            }
            else if (i == 5)
            {
                Console.WriteLine("1부터 10까지의 합은");
                int sum = 0;

                for (int k = 1; k <= 10; k++)
                {
                    sum = sum + k;
                }
                Console.WriteLine(sum);

            }
            else if (i == 6)
            {
                int[] subject = new int[3];

                Console.WriteLine("국어 점수를 입력하세요");
                subject[0] = Convert.ToInt32(Console.ReadLine());

                Console.WriteLine("영어 점수를 입력하세요");
                subject[1] = Convert.ToInt32(Console.ReadLine());

                Console.WriteLine("수학 점수를 입력하세요");
                subject[2] = Convert.ToInt32(Console.ReadLine());

                int total = 0;

                for (int k = 0; k < 3; k++)
                {
                    total = total + subject[k];
                }
                Console.WriteLine("총점은 {0}점 입니다.", total);
                Console.WriteLine("평균점수는 {0}점 입니다.", total / 3);
            }
            else if (i == 7)
            {
                double num1;
                double num2;
                double num3;
                Console.WriteLine("첫번째 실수를 입력하세요.");
                num1 = Convert.ToDouble(Console.ReadLine());
                Console.WriteLine("두번째 실수를 입력하세요.");
                num2 = Convert.ToDouble(Console.ReadLine());

                num3 = SumVal(num1, num2);
                Console.WriteLine("두 수 {0}과 {1}의 합은 {2}입니다.", num1, num2, num3);


            }
            else if (i == 8)
            {

            } SubjectScore ss;
            Console.WriteLine("국어, 수학, 영어 점수를 각각 입력하세요.");
            ss.lang = Convert.ToDouble(Console.ReadLine());
            ss.math = Convert.ToDouble(Console.ReadLine());
            ss.eng = Convert.ToDouble(Console.ReadLine());
            Console.WriteLine("과목의 합은 {0}입니다.", ss.lang + ss.math + ss.eng);
        }




        static double SumVal(double val1, double val2)
        {
            double sum;
            sum = val1 + val2;
            return sum;
        }



    }
}