View Code of Problem 48

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