View Code of Problem 71

#include<stdio.h>
int main()
{
	int a[1000]={0},n,i; 
	double sum=0;
	a[0]=1;
	a[1]=2;
	scanf("%d",&n);
	for(i=2;i<=n;i++)
	{
		a[i]=a[i-2]+a[i-1];
	}
	for(i=0;i<=n;i++)
	{
		sum+=(double)a[i+1]/a[i];
	}	
	
	printf("%.2lf",sum);
}