面试会遇到的几个小程序

面试会遇到的几个小程序：

1.有数列如下：1，1，2，3，5，8，13，。。。，请第N位？（请用两种方法得到第N位是多少，并可查询任意一位是多少）

        //斐波那契数
        private static List<long> GetNum(long n)
        {
long a = 1, b = 1, num = 0;
            List<long> resultArry = new List<long>();
try
            {
for (int i = 0; i < n; i++)
                {
                    num = a + b;
                    a = b;
                    b = num;
                    resultArry.Add(num);
                }
            }
catch (Exception ex)
            {
throw new Exception(ex.Message);
            }
return resultArry;
        }

　　

static long i = 0, j = 1, result = 0;
static List<long> resultArry = new List<long>();
private static long ReturnNum(long n)
        {
if (n <= 2)
            {
                result = i + j;
            }
else
            {
                result = ReturnNum(n - 1) + ReturnNum(n - 2);
            }

if (!resultArry.Contains(result))
            {
                resultArry.Add(result);
            }
return result;
        }

　　

static void Main(string[] args)
        {
//方法一：
            List<long> resultArry = GetNum(10);
foreach (long result in resultArry)
            {
                 Console.Write(result+",");
            }

//方法二
//ReturnNum(10);
//resultArry.Insert(0, 1);
//foreach (long result in resultArry)
// {
//      Console.Write(result+",");
//}

             Console.Read();
        }