Mine

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <mpi.h>

#define MASTER 0
#define IS_MASTER my_id==0

typedef struct {
	int cols;
	int rows;
	float *data;
} MATRIX;

MATRIX create_matrix(int rows, int cols) {
	MATRIX m;

	m.rows = rows;
	m.cols = cols;

	m.data = ( float * ) malloc( sizeof( float ) * rows * cols );

	return m;
}

void read_matrix( char *path, MATRIX *mat ) {
	int i, j;

	char aux_string[50];
	char rows_string[10], cols_string[10];

	FILE *input_file = fopen( path, "r" );

	fgets( aux_string, 50, input_file );
	printf( "Leyendo la matriz: %s", aux_string );

	fgets( aux_string, 50, input_file );
	sscanf( aux_string, "%s %s", rows_string, cols_string );

	printf( "dimensiones: %s x %s\n\n", rows_string, cols_string );

	*mat = create_matrix( atoi( rows_string ), atoi( cols_string ) );

	for( i = 0; i < mat->rows; i++ )
		for( j = 0; j < mat->cols; j++ )
			fscanf( input_file, "%f", &mat->data[i * mat->cols + j] );

	
}

void broadcast_matrix(MATRIX *m, int my_id) {
	int rows, cols;

	rows = m->rows;
	cols = m->cols;

	MPI_Bcast( &rows, 1, MPI_INT, MASTER, MPI_COMM_WORLD );
	MPI_Bcast( &cols, 1, MPI_INT, MASTER, MPI_COMM_WORLD );
	
	if(IS_MASTER)
		MPI_Bcast( m->data, rows * cols, MPI_FLOAT, MASTER, MPI_COMM_WORLD );
	else {
		*m = create_matrix( rows, cols );
		MPI_Bcast( m->data, rows * cols, MPI_FLOAT, MASTER, MPI_COMM_WORLD );
	}
}

int main( int argc, char *argv[] ) {
	MATRIX mat1, mat2;
	MPI_Status status;
	int total_procs, my_id;
	int i, j;

	/*
	if(argc != 3) {
		printf("Uso del programa: nombre_del_ejecutable 1ra_matriz 2da_matriz\n");

		return 1;
	}*/
	
	MPI_Init( &argc, &argv );
	MPI_Comm_size( MPI_COMM_WORLD, &total_procs );
	MPI_Comm_rank( MPI_COMM_WORLD, &my_id );

	if(IS_MASTER) {
		read_matrix( "mat1", &mat1 );
		read_matrix( "mat2", &mat2 );

		// SHOW LA 1ra MATRIZ 
		for(i = 0; i < mat1.rows; i++) {
			for(j = 0; j < mat1.cols; j++)
				printf("%f ", mat1.data[i * mat1.cols + j]);
			printf("\n");
		}
		printf("\n");

		// SHOW LA 2da MATRIZ
		for(i = 0; i < mat2.rows; i++) {
			for(j = 0; j < mat2.cols; j++)
				printf("%f ", mat2.data[i * mat2.cols + j]);
			printf("\n");
		}
	}
	broadcast_matrix( &mat2, my_id );
	
	MPI_Finalize();

	return 0;
}