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

main() {
double cur, inv,sum1,sum2;
int i;
	inv = cur = sum1 = sum2 = 0.0;
for (i=1;i<16;i++) {
	sum1 += inv = 1.0/sqrt(i);
	printf("i=%d inv=%f sum2=%f\n",i,inv,sum1);
	sum2 += cur = 2.0 * (1.0/sqrt(i))/3.0;
	printf("i=%d cur=%f sum2=%f\n",i,cur,sum2);
	}
}