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

/*   gcc -fopenmp -o aufg3 aufg3.c -lgomp; OMP_NUM_THREADS=7 ./aufg3   */

int main(int argc, char *argv[])
{
    int i, N;
    double h, x, sum, PI;

    N = 1999999999;

    h = 1.0/N;
    sum = 0;

    time_t start, end;
    time(&start);

#pragma omp parallel private (i,x) shared (N,h,sum)
{
#pragma omp for reduction (+:sum) schedule (static) nowait
    for ( i=1 ; i<=N ; i++ ) {
        x = h * (i - 0.5);
        sum = sum + 4/( 1 + x*x );
    }
}

    time(&end);
    printf("Dauer: %.2lf Sekunden", difftime(end, start));

    PI = h * sum;

    printf(" PI = %f\n",PI);
    printf(" woozaaa");

}