#include <stdio.h>
#include <stdarg.h>
#include <time.h>
#include "MacMP.h"
#define NINT 1000000000

int main(void);
void adder(int *, int *, double *, double *);

int main ()
/* This program calculates the variance of the first 10^9 integers     */
/* using both cpus on the dual processor Macintosh.                    */
/* To compile with the Absoft C compiler, use:                         */
/* acc -A -O adder.c MacMP.c "{SharedLibraries}"MPLibrary -o adder.out */
{
int n=NINT, n1=NINT/2, n2=NINT, start1=0, start2=NINT/2;
clock_t start_program, end_program;
double sum11, sum12, sum21, sum22, mean, mesq;
int idtask, nproc, nargs=4;
typedef void (*aProcPtr)();
start_program = clock ();

MP_Init(&nproc);
/* Use second cpu to compute partial sums for second group */
MP_Taskstart(&idtask,(aProcPtr)&adder,&nargs,&n2,&start2,&sum21,&sum22);
/* Use main cpu to compute partial sums for first group */
adder (&n1, &start1, &sum11, &sum12);
/* Wait for second cpu to complete */
MP_Taskwait(&idtask);
MP_End();

/* Add partial sums together */
mean = (sum11 + sum21) / n;
mesq = (sum12 + sum22) / n;

printf("%15d %20.3f %20.3f\n", n, mean, mesq - (mean * mean));

end_program = clock ();
printf("\ntime in sec: %7.2f\n", (end_program-start_program)/60.);
return 1;
}



void
adder (int *n, int *start, double *s1, double *s2)
{
int i;
double ls1 = 0.0, ls2 = 0.0;
for (i=(*start);i<(*n);i++)
   {
      ls1+=(double) i;
      ls2+=(double) i*i;
   }
*s1 = ls1;
*s2 = ls2;
}