using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication28
{
    public class Chengfa
    {
         int x=0;
         int X=0;
        private int a;
        private int b;
        public int A
        {
            get { return a; }
            set { a = value; }
        }
        public int B
        {
            get { return b; }
            set { b = value; }
        }
        public void timu()
        {
            Random r = new Random();
            a = r.Next(0, 10);
            b = r.Next(0, 10);
            Console.WriteLine(a+"和"+b+"的乘积是多少？" );
        }
        public void zhengque()
        {
            int c = int.Parse(Console.ReadLine());
            for (int i = 0; i < 99; i++)
            {
                X++;
                if (a * b == c)
                {
                    Console.WriteLine("非常棒");
                    break;
                }
                else
                {
                    Console.WriteLine(a + "和" + b + "的乘积是多少？");
                    this.zhengque();
                    break;
                }
            }
            if (X == 1)
            {
                x=x+1;
            }
    }
        public void zhengquelv()
        {
            float  l = x / 10f;
            if (l < 0.75)
            {
                Console.WriteLine("正确率为{0},请你的老师给你辅导一下",l);
            }
            else
            {
                Console.WriteLine("正确率为{0}", l);
            }
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            Chengfa chengfa = new Chengfa();         
            for (int n = 0; n < 10; n++)
            {
                chengfa.timu();
                chengfa.zhengque();
            }
            chengfa.zhengquelv();
            Console.ReadKey();
        }
    }
}
以上是我的作业
问题是x在自增时数据丢失，这个怎么修改

有一个要求是如果输入的答案不对，要将这个式子再次出现直至答案为对为止，所以不是输入100次，这一百次只是个循环这个式子，一千次一万次都无所谓的，我发了一个附件，里面有作业要求，也怪我没注释