View Code of Problem 48

#include<stdio.h>
int main()
{
	double sum=0,a=2,b=1,c=0;
	int n=0;
	scanf("%d",&n);
	for(int i=0;i<n;i++)
	{
		sum+=a/b;
		c=a;
		a=a+b;
		b=c;
	}
	printf("%.6lf",sum);
}