#include  #include  #include "omp.h" int main(int argc, char *argv[]) { int NUM_THREADS = 2; int SPACING = 1; if (argc == 3) { NUM_THREADS = atoi(argv[1]); SPACING = atoi(argv[2]); } if (NUM_THREADS == 0 || SPACING == 0) { std::cerr << "ERROR: invalid command line" << std::endl; exit(1); } int *array = new int[NUM_THREADS*SPACING]; for (int i = 0; i < NUM_THREADS; i++) array[i*SPACING] = 0; struct timeval tv1, tv2; gettimeofday(&tv1, 0); #pragma omp parallel num_threads(NUM_THREADS) { int index = omp_get_thread_num() * SPACING; for(int i = 0; i < 1e9; i++) array[index]++; } gettimeofday(&tv2, 0); std::cout << "Time: " << (double)(tv2.tv_usec - tv1.tv_usec) / 1000000 + (double)(tv2.tv_sec - tv1.tv_sec) << std::endl; delete[] array; return 0; }

Now the integers in array do not have to be next to each other. Instead they have indexes that are a multiple of SPACING. Again, write a script that runs the above code, but this time vary the Spacing by 1 from 1 to 20 while keeping the number of threads at two. Write this script in bash