View Code of Problem 71

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>

int main() {
	int n,i;
	scanf("%d",&n);
	double a=1.0,b=2.0,sum1;
	double sum=0.0;
	for(i=1;i<=n;i++){
		sum1=a+b;
		sum=sum+b/a;
		a=b;
		b=sum1;
	}
	printf("%.2lf",sum);
}