using System;
public class Program
{
public void Main()
int Num =10;
fff(Num);
}
public void fff (int Num) //定義function功能
int p1 = 1; // 第一個數
int p2 = 1; // 第二個數
int res = 0;
for (int i = 3; i <= Num; i++)
res = p1 + p2;
p1 = p2;
p2 = res;
Console.WriteLine(res+"\n");