//有一分数序列:2/1,3/2,5/3,8/5,13/8,21/13...求出这个数列的前20项之和;
using System;
namespace Program
{
public class QiuHe
{
public static void FirstTest()
{
double a = 1;
double b = 1;
double fraction = a/b;
double Sn = 0;
for(int i=0;i<20;i++)
{
double t1 = a;
double t2 = b;
a = t1+t2;
b = t1;
fraction = a/b;
Sn += fraction;
}
Console.WriteLine(Sn);
}
}
}
//编写一个应用程序,接受用户输入的一行字符串,判断该字符串是否是回文数?
using System;
namespace Program1
{
public class ShuRu
{
public static void Test()
{
string s = "";
int a = 0;
Console.WriteLine("请输入一个字符串");
s = Console.ReadLine();
char[] b = s.ToCharArray();
for(int i=0;i<b.Length/2;i++){
if(b[i]!=b[s.Length-i-1]){
a = 1;
}
}
if(a==1){
Console.WriteLine("该字符串不是回文字符串");
} else {
Console.WriteLine("该字符串是回文字符串");
}
}
}
}
namespace Program2
{
class Program
{
static void Main(string[] args)
{
Test2.Test();
}
}
}