C#求一个数N的阶乘

Question

如题所述

Answer 1

            Console.WriteLine("请输入一个正整数:");
            int num = Convert.ToInt32(Console.ReadLine());
            if (num <= 0)
            {
                Console.WriteLine("输入的整数不正确");
                Console.ReadLine();
                return;
            }
            int sum = 1;
            for (int i = 1; i <= num; i++)
            {
                sum = sum * i;
            }
            Console.WriteLine(num + "的阶乘是" + sum.ToString());
            Console.ReadLine();