2、从键盘上输入两个整数，由用户回答它们的和，差，积，商和取余运算结果，并统计出正确答案的个数。

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;
namespace project2

{

    class Program

    {

        static void Main(string[] args)

        {

            int i = 0;

            Console.WriteLine("please enter a integer");

            int x = int.Parse(Console.ReadLine());                                                 //将Console.ReadLine()得出来的字符串转换为整型(int)

            Console.WriteLine("please ener anther integer");

            int y = int.Parse(Console.ReadLine());

            int sum = x + y;

            int difference = x - y;

            int product = x * y;

            int quotient = x / y;

            int remainder = x % y;

            Console.WriteLine("please answer their sum:");

            int he = int.Parse(Console.ReadLine());

            if(he==sum)

            {

                i++;

            }

            Console.WriteLine("please answer the difference:");

            int cha=int.Parse(Console.ReadLine());

            if(cha==difference)

            {

                i++;

            }

            Console.WriteLine("please answer the product:");

            int chengji = int.Parse(Console.ReadLine());

            if(chengji==product)

            {

                i++;

            }

            Console.WriteLine("please answer the quotient:");

            int shang = int.Parse(Console.ReadLine());

            if(shang==quotient)

            {

                i++;

            }

            Console.WriteLine("please answer the remainder:");

            int yu = int.Parse(Console.ReadLine());

            if(yu==remainder)

            {

                i++;

            }

            Console.WriteLine("the correct answer number:{0}",i);

            Console.ReadKey();

        }

    }

}