C#学习笔记（求500内偶数合，学习for、while、do/while循环）

这一次的任务是计算500之内的偶数合。

代码：

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

namespace c4_t3
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("分别使用for、while、do/while语句求500以内偶数合。");
            Console.WriteLine("for语句结果:{0}",qo_for());
            Console.WriteLine("while语句结果:{0}", qo_while());
            Console.WriteLine("do/while语句结果:{0}", qo_dowhile());
            System.Threading.Thread.Sleep(1000000);
        }
        static int qo_for()
        {
            int i,sum=0;
            for (i=0;i<=500;i+=2)
            {
                sum+=i;
            }
            return sum;
        }

        static int qo_while()
        {
            int i=0,sum=0;
            while (i <= 500)
            {
                if (i % 2 == 0)
                    sum += i;
                i++;
            }
            return sum ;
        }
        
        static int qo_dowhile()
        {
            int i = 0, sum = 0;
            do
            {
                if (i % 2 == 0)
                    sum += i;
                i++;
            } while (i < 501);
            return sum;
        }
    }
}