View Code of Problem 71

#include<bits/stdc++.h>
using namespace std;
int main() {
	double a[50],b[50];
	a[1]=2,a[2]=3;
	b[1]=1,b[2]=2;
	for(int i=3;i<50;i++){
		a[i]=a[i-1]+a[i-2];
		b[i]=b[i-1]+b[i-2];
	}
	int x;
	double sum=0;
	cin>>x;
	for(int i=1;i<=x;i++){
		sum+=a[i]/b[i];
	}
	cout<<fixed<<setprecision(2)<<sum;
	return 0;
}