View Code of Problem 71

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