/* pi = 3.14159265358979323846 */
#include <stdio.h>
#define NPTS 2000000
#define NLOOP 100
double a,b,c,x[NPTS+1];
int i,loop;
main() {
    a = 0.5;
    b = 0.75;
    c = 0.25;
    for (loop = 1; loop <= NLOOP; ++loop) {
       x[0] = 0;
       for (i = 1; i <= NPTS; ++i)
          x[i] = x[i-1] + a/((i-b)*(i-c)); }
    printf("pim.c: NPTS, nloop = %d, %d\n",NPTS,NLOOP);
    printf("pi = %.20f\n",x[NPTS]);
    }