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  1. #include <pthread.h>
  2. #include <stdio.h>
  3. #include <stdlib.h>
  4. #include <time.h>
  5. #define size 10
  6. #define M size
  7. #define K size
  8. #define N size
  9.  
  10. // int A [M][K] = { {1,4}, {2,5}, {3,6} };
  11. // int B [K][N] = { {8,7,6}, {5,4,3} };
  12.  
  13. int A [M][K];
  14. int B [K][N] ;
  15. int C [M][N];
  16.  
  17. struct v {
  18.    int i; /* row */
  19.    int j; /* column */
  20. };
  21.  
  22. void *runner(void *param); /* the thread */
  23.  
  24. void fill_matrix(int matrix[][N], int row, int column)
  25. {
  26.    // int (*matrix)[row] = malloc(sizeof(int[row][column]));
  27.   for (int i = 0; i < row; i++)
  28.   {
  29.     for (int j = 0; j < column; j++)
  30.     {
  31.       matrix[i][j] = (rand() % (100-0+1)) + 1;
  32.     }
  33.   }
  34.   return;
  35. }
  36.  
  37. int main(int argc, char *argv[]) {
  38.  
  39.    int i,j, count = 0;
  40.    // int (*A)[M] = malloc(sizeof(int[M][K]));
  41.    // int (*B)[K] = malloc(sizeof(int[K][N]));
  42.    // A = (int*)malloc(sizeof(A));
  43.  
  44.    fill_matrix(A,M,K);
  45.    fill_matrix(B,K,N);
  46.    clock_t start = clock();
  47.   // pthread_t thread_array[M*N];
  48.     pthread_t thread_array[M*N]; //malloc(M*N * sizeof(pthread_t));
  49.  
  50.     pthread_attr_t attr;
  51.     pthread_attr_init(&attr);
  52.    for(i = 0; i < M; i++) {
  53.       for(j = 0; j < N; j++) {
  54.          //Assign a row and column for each thread
  55.          struct v *data = (struct v *) malloc(sizeof(struct v));
  56.          data->i = i;
  57.          data->j = j;
  58.          /* Now create the thread passing it data as a parameter */
  59.          //pthread_t tid;       //Thread ID
  60.          //pthread_attr_t attr; //Set of thread attributes
  61.          //Get the default attributes
  62.          //pthread_attr_init(&attr);
  63.          //Create the thread
  64.  
  65.          pthread_create(&thread_array[count],&attr,runner,data);
  66.          //Make sure the parent waits for all thread to complete
  67.          //pthread_join(tid, NULL);
  68.          count++;
  69.       }
  70.    }
  71.    for(int k =0;k<M*N;k++){
  72.    pthread_join(thread_array[k],NULL);
  73.    }
  74.      clock_t end = clock();
  75.      printf("%f\n",(float)(end-start)/CLOCKS_PER_SEC );
  76.  
  77.    //Print out the resulting matrix
  78.    //for(i = 0; i < M; i++) {
  79.    //   for(j = 0; j < N; j++) {
  80.    //      printf("%d ", C[i][j]);
  81.    //   }
  82.    //   printf("\n");
  83.   // }
  84. }
  85.  
  86. //The thread will begin control in this function
  87. void *runner(void *param) {
  88.    struct v *data = param; // the structure that holds our data
  89.    int n, sum = 0; //the counter and sum
  90.  
  91.    //Row multiplied by column
  92.    for(n = 0; n< K; n++){
  93.       sum += A[data->i][n] * B[n][data->j];
  94.    }
  95.    //assign the sum to its coordinate
  96.    C[data->i][data->j] = sum;
  97.  
  98.    //Exit the thread
  99.    pthread_exit(0);
  100. }
Success #stdin #stdout 0s 4440KB
comments ()
stdin 
Standard input is empty
stdout 
0.000482
https://ideone.com/1r0e2V
language:
C99 (gcc 8.3)
created:
4 years ago
visibility:
public

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