#include

#include

#include“mpi.h“

#include“stdio.h“

#include

const?int?rows?=?3;?/*the?rows?of?matrix*/

const?int?cols?=?3;?/*the?cols?of?matrix*/

int?main（int?argc?char?**argv）



{

int?ijkmyidnumprocsanstag;

double??A[rows][cols]B[cols]X[rows]AB[rows][cols+1];

int?masterpro;

double?buf[cols+1];

double?starttimeendtime;

double?tmptotaltime;

srand（（unsigned?int）time（NULL））;

MPI_Status?status;

masterpro?=?0;

MPI_Init（&argc&argv）;

MPI_Comm_rank（MPI_COMM_WORLD&myid）;

MPI_Comm_size（MPI_COMM_WORLD&numprocs）;

if?（myid==0）

????{

??????starttime?=?MPI_Wtime（）;

??????printf（“please?input?xishu“）;

??????for（i=0;i
?????????{

????????????for（j=0;j
?????????????????{

????????????????????scanf（“%lf“&A[i][j]）;

?????????????????}

??????????}

??????printf（“please?input?changshu“）;

	for（i=0;i
?????	??{

	????scanf（“%lf“&B[i]）;

	??}

	?for?（i=0;i
??????????{



?????????????AB[i][cols]=B[i];

?????????????for（j=0;j
?????????????AB[i][j]=A[i][j];

???????????}

?????	?printf（“zengguang\n“）;

?????	?for（i=0;i
		{

?????????????	?for（j=0;j
?????????????	?printf（“%.2f?“AB[i][j]）;

?????????????	?printf（“\n“）;

???????????	}	

???}

int?x;

double?coe;

for（x=0;x
???{

???????MPI_Bcast（&AB[x][0]cols+1MPI_DOUBLE0MPI_COMM_WORLD）;

???????if（myid==0）

????????????{

??????????????for（i=1;i
????????????????{

??????????????????for（k=x+1+i;k
??????????????????MPI_Send（&AB[k][0]cols+1MPI_DOUBLEi0MPI_COMM_WORLD）;

????????????????}

???????????????for（k=x+1;k
?????????????????{

???????????????????coe=AB[k][x]/AB[x][x];

???????????????????for（j=x;j
??????????????????????{

???????????????????????AB[k][j]-=AB[x][j]*coe;

??????????????????????}

??????????????????}

???????????????for（i=1;i
??????????????????{

????????????????????for（k=x+1+i;k
????????????????????{

?????????????????????MPI_Recv（&AB[k][0]cols+1MPI_DOUBLEi1MPI_COMM_WORLD&status）;

????????????????????}

??????????????????}

???