static void Main(string[] args)
        {
            float x, y, z, temp;
            Console.Write("请输入一个实数：");
            x = float.Parse(Console .ReadLine() );
            Console.Write("请输入一个实数:");
            y = float.Parse(Console .ReadLine ());
            Console.Write("请输入一个实数:");
            z = float.Parse(Console .ReadLine ());
            temp = x >= y ? x : y;
            temp = temp >= z ? temp : z;
            Console.Write("最大数为:{0}",temp );
            Console.Read();
            Console.ReadLine();
        }