1.     #include <math.h>
2.     #include <mpi.h>
3.     #include <stdio.h>
4.     #include <unistd.h>
5.     #define NUM_TRAPEZOIDS 10000000000
6.     __attribute__((target(mic))) inline double f(double x) {
7.         return 1.00*x*x*exp(-(x-0.0)*(x-0.0)/(2.0*0.25*0.25))
8.             + 0.50*x*x*exp(-(x-0.2)*(x-0.2)/(2.0*0.50*0.50))
9.             + 0.50*x*x*exp(-(x+0.2)*(x+0.2)/(2.0*0.50*0.50))
10.            + 0.25*x*x*exp(-(x-0.4)*(x-0.4)/(2.0*1.00*1.00))
11.            + 0.25*x*x*exp(-(x+0.4)*(x+0.4)/(2.0*1.00*1.00));
12.    }
13.    
14.    int main (int argc, char *argv[]) {
15.        int namelen, rank, size;
16.        char name[MPI_MAX_PROCESSOR_NAME];
17.        double upper_bound = 5.0, lower_bound = -5.0;
18.        double x0, x1, width;
19.        double integral = 0;
20.        double compute_time, total_time;
21.        int chunk_size;
22.        MPI_Init(&argc, &argv);
23.        MPI_Comm_size(MPI_COMM_WORLD, &size);
24.        MPI_Comm_rank(MPI_COMM_WORLD, &rank);
25.        MPI_Get_processor_name(name, &namelen);
26.        chunk_size = NUM_TRAPEZOIDS / size;
27.        x0 = lower_bound+(upper_bound-lower_bound)*rank/size;
28.        x1 = x0 + (upper_bound - lower_bound)/size;
29.        width = (x1-x0)/chunk_size;
30.        MPI_Barrier(MPI_COMM_WORLD);
31.        compute_time = total_time = MPI_Wtime();
32.    #pragma offload target(mic)
33.    #pragma omp parallel
34.    #pragma omp for reduction(+:integral)
35.        for (int i = 0; i < chunk_size ; i++) {
36.            integral += 0.5*width *(f(x0+width*i)+f(x0+width*(i+1)));
37.        }
38.        compute_time = MPI_Wtime() - compute_time;
39.        MPI_Allreduce(MPI_IN_PLACE, &integral, 1, MPI_DOUBLE, MPI_SUM, 
      MPI_COMM_WORLD); 
40.        total_time = MPI_Wtime() - total_time;
41.        printf("rank %d of %d on %s: %f seconds\n", rank, size, name, 
      compute_time); 
42.        if (rank == 0) {
43.            printf("integral = %f, time = %f\n", integral, total_time);
44.        }
45.        MPI_Finalize();
46.        return(0);
47.    }