multithreading - Addition of a matrix using thread in c -


the question add 2 matrix using thread,where loop takes row element of 2 matrix , thread creates thread add individual elements. below code --

#include<stdio.h> #include<pthread.h> #include<error.h> #include<stdlib.h> #define r 2 #define c 3 struct mat{     int (*a)[r][c];     int (*b)[r][c];     int (*d)[r][c];     int m, n; }; struct element{     int *a;     int *b;     int *d; }; void* add_element(void* pelement){     struct element* e1 = pelement;     (*e1).d = (*e1).a + (*e1).b;     pthread_exit(null); } void* add_row(void* pmat){     struct mat *mat1 = pmat;     int = 0, m = mat1->m, n = mat1->n;     for(i = 0; < n; ++i){         pthread_t add_e;         struct element e1;         e1.a = (*mat1->a)[m][i];         e1.b = (*mat1->b)[m][i];         e1.d = (*mat1->d)[m][i];         if(pthread_create(&add_e, null, add_element, &e1) != 0){             perror("unable create thread\n");             exit(0);         }         (*mat1->d)[m][i] = e1.d;         pthread_join(add_e, null);         //(*(*mat1).d)[m][i] = (*(*mat1).a)[m][i] + (*(*mat1).b)[m][i];     }     pthread_exit(0); } int main() {     int a[r][c] = {1, 2, 3, 4, 5, 6};     int b[r][c] = {1, 2, 3, 4, 5, 6};     int d[r][c] = {0, 0, 0, 0, 0, 0};     pthread_t add_mat[r];     struct mat mat1;     mat1.a = &a;     mat1.b = &b;     mat1.d = &d;     int = 0;     for(i = 0; < r; ++i){         mat1.m = i;         mat1.n = c;         if(pthread_create(&add_mat[i], null, add_row, &mat1) != 0){             perror("unable create thread\n");             exit(1);         }         pthread_join(add_mat[i], null);     }     for(i = 0; < r; ++i){         int j = 0;         for(j = 0; j < c; ++j)             printf("%d ", d[i][j]);         printf("\n");     }     pthread_exit(null); }

while executing, doing wrong pointer. error --

add_matrix.c: in function ‘add_element’: add_matrix.c:20:20: error: invalid operands binary + (have ‘int *’ , ‘int *’)   (*e1).d = (*e1).a + (*e1).b;

how can handle pointer in order result? edit have solved it. please ignore it.


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