View Code of Problem 48

int main(){
	int i,n,fenzi=2,fenmu=1,temp;
	scanf("%d",&n);
	double a[n],sum=0;
	for(i=0;i<n;i++){
		a[i]=(double)fenzi/(double)fenmu;
		temp=fenmu;
		fenmu=fenzi;
		fenzi=temp+fenzi;
		sum+=a[i];
	} 
	printf("%0.6lf",sum);
}