View Code of Problem 71

#include<stdio.h>
#include<string.h>
#include<math.h>
#define MAX 1000000+10
#define Max(a,b) a>b?a:b
#define Min(a,b) a<b?a:b
int main()
{
	int n;
	scanf("%d",&n);
	int  a,b;
	a=1.0;
	b=2.0;
	int i;
	double sum=0.0;
	for(i=0;i<n;i++)
	{
	
		sum+=1.0*b/a;
		b=a+b;
		a=b-a;
	}
	printf("%.2lf",sum);

}