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  1. #include <mpi.h>
  2. #include <omp.h>
  3. #include <stdio.h>
  4. #include <stdlib.h>
  5. #include <time.h>
  6.  
  7. int main(int argc, char** argv) {
  8.     int rank, size, N, M, *array = NULL, local_sum = 0, global_sum = 0;
  9.  
  10.     // Initialize MPI
  11.     MPI_Init(&argc, &argv);
  12.     MPI_Comm_rank(MPI_COMM_WORLD, &rank);
  13.     MPI_Comm_size(MPI_COMM_WORLD, &size);
  14.  
  15.     if (rank == 0) {
  16.         // Input M and N
  17.         printf("Enter the number of processes (M): ");
  18.         scanf("%d", &M);
  19.         printf("Enter the size of the array (N): ");
  20.         scanf("%d", &N);
  21.  
  22.         if (M > size) {
  23.             printf("Error: M cannot be greater than the total number of MPI processes.\n");
  24.             MPI_Abort(MPI_COMM_WORLD, 1);
  25.         }
  26.  
  27.         // Initialize the array with random integers
  28.         array = (int*)malloc(N * sizeof(int));
  29.         srand(time(0));
  30.         for (int i = 0; i < N; i++) {
  31.             array[i] = rand() % 100;
  32.         }
  33.     }
  34.  
  35.     // Broadcast N to all processes
  36.     MPI_Bcast(&N, 1, MPI_INT, 0, MPI_COMM_WORLD);
  37.  
  38.     // Scatter the array to all processes
  39.     int local_size = N / size;
  40.     int* local_array = (int*)malloc(local_size * sizeof(int));
  41.     MPI_Scatter(array, local_size, MPI_INT, local_array, local_size, MPI_INT, 0, MPI_COMM_WORLD);
  42.  
  43.     // Compute the partial sum using OpenMP
  44.     #pragma omp parallel for reduction(+:local_sum)
  45.     for (int i = 0; i < local_size; i++) {
  46.         local_sum += local_array[i];
  47.     }
  48.  
  49.     // Reduce all partial sums to the global sum in Process 0
  50.     MPI_Reduce(&local_sum, &global_sum, 1, MPI_INT, MPI_SUM, 0, MPI_COMM_WORLD);
  51.  
  52.     if (rank == 0) {
  53.         printf("Total Sum of Array: %d\n", global_sum);
  54.         free(array);
  55.     }
  56.  
  57.     free(local_array);
  58.     MPI_Finalize();
  59.     return 0;
  60. }
  61.  
Success #stdin #stdout #stderr 0.26s 40856KB
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Standard input is empty
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Standard output is empty
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Error: unexpected symbol in "int main"
Execution halted
https://ideone.com/JPOr4w
language:
R (R 3.5.2)
created:
1 day ago
visibility:
public

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