n 的阶乘的和：using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace jiechengDemo{ class Program { public static long jiecheng(int n) { if (n == 0) return 1; else return n * jiecheng(n - 1); } static void Main(string[] args) { Console.Write("enter n:"); int n = int.Parse(Console.ReadLine()); long sum = 0; for (int i = 1; i <= n; i++) { sum += jiecheng(i); } Console.WriteLine(sum.ToString()); Console.Read();}}}冒泡排序：using System;using System.Collections.Generic;using System.Text;namespace maopaopaixu{ public class SelectionSorter { private int min; public void Sort (int [] list) { for(int i=0;i
