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  1. #include <mpi.h>
  2. #include <stdio.h>
  3. #include <stdlib.h>
  4. #include <time.h>
  5.  
  6. #define MATRIX_SIZE 100
  7. #define VECTOR_SIZE 100
  8.  
  9. int main(int argc, char** argv) {
  10.     int rank, size;
  11.     int matrix[MATRIX_SIZE][MATRIX_SIZE];
  12.     int vector[VECTOR_SIZE];
  13.     int local_matrix[MATRIX_SIZE / size][MATRIX_SIZE];
  14.     int local_vector[VECTOR_SIZE / size];
  15.     int local_result[MATRIX_SIZE / size];
  16.     int result[MATRIX_SIZE];
  17.  
  18.     // Initialize MPI
  19.     MPI_Init(&argc, &argv);
  20.     MPI_Comm_rank(MPI_COMM_WORLD, &rank);
  21.     MPI_Comm_size(MPI_COMM_WORLD, &size);
  22.  
  23.     // Generate matrix and vector
  24.     if (rank == 0) {
  25.         srand(time(NULL));
  26.         for (int i = 0; i < MATRIX_SIZE; i++) {
  27.             for (int j = 0; j < MATRIX_SIZE; j++) {
  28.                 matrix[i][j] = rand() % 100;
  29.             }
  30.         }
  31.         for (int i = 0; i < VECTOR_SIZE; i++) {
  32.             vector[i] = rand() % 100;
  33.         }
  34.     }
  35.  
  36.     // Scatter matrix and vector
  37.     MPI_Scatter(matrix, MATRIX_SIZE * MATRIX_SIZE / size, MPI_INT, local_matrix,
  38.                 MATRIX_SIZE * MATRIX_SIZE / size, MPI_INT, 0, MPI_COMM_WORLD);
  39.     MPI_Scatter(vector, VECTOR_SIZE / size, MPI_INT, local_vector,
  40.                 VECTOR_SIZE / size, MPI_INT, 0, MPI_COMM_WORLD);
  41.  
  42.     // Perform local matrix-vector multiplication
  43.     for (int i = 0; i < MATRIX_SIZE / size; i++) {
  44.         local_result[i] = 0;
  45.         for (int j = 0; j < MATRIX_SIZE; j++) {
  46.             local_result[i] += local_matrix[i][j] * local_vector[j];
  47.         }
  48.     }
  49.  
  50.     // Gather local results to obtain final result
  51.     MPI_Gather(local_result, MATRIX_SIZE / size, MPI_INT, result,
  52.                MATRIX_SIZE / size, MPI_INT, 0, MPI_COMM_WORLD);
  53.  
  54.     // Print result
  55.     if (rank == 0) {
  56.         printf("Matrix:\n");
  57.         for (int i = 0; i < MATRIX_SIZE; i++) {
  58.             for (int j = 0; j < MATRIX_SIZE; j++) {
  59.                 printf("%d ", matrix[i][j]);
  60.             }
  61.             printf("\n");
  62.         }
  63.         printf("Vector:\n");
  64.         for (int i = 0; i < VECTOR_SIZE; i++) {
  65.             printf("%d ", vector[i]);
  66.         }
  67.         printf("\nResult:\n");
  68.         for (int i = 0; i < MATRIX_SIZE; i++) {
  69.             printf("%d ", result[i]);
  70.         }
  71.         printf("\n");
  72.     }
  73.  
  74.     // Finalize MPI
  75.     MPI_Finalize();
  76.  
  77.     return 0;
  78. }
  79.  
  80.  
Success #stdin #stdout #stderr 0.28s 39152KB
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stdin
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Standard input is empty
stdout
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Standard output is empty
stderr
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Error: unexpected symbol in "int main"
Execution halted
https://ideone.com/0efrRU
language:
R (R 3.5.2)
created:
2 years ago
visibility:
public

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