求斐波拉契数列的项

//斐波拉契1,1,2,3,5,8...
#include
int main()
{
	int f1,f2,f3;
	int n;
	int i;
	f1=1;
	f2=1;
	printf("请输入数的序号：");
	scanf("%d",&n);
	if (1==n)
	{
		f3=1;
	}
	else
	{
		for (i=3;i<=n;++i)
		{
			f3=f2+f1;
			f1=f2;
			f2=f3;			
		}
	}
	printf("fn=%d\n",f3);
	return 0;
 }