#?include?
#?include?
#?include?
#?include?

int?main?（?void?）;
double?cpu_time?（?void?）;
void?daxpy?（?int?n?double?da?double?dx[]?int?incx?double?dy[]?int?incy?）;
double?ddot?（?int?n?double?dx[]?int?incx?double?dy[]?int?incy?）;
int?dgefa?（?double?a[]?int?lda?int?n?int?ipvt[]?）;
void?dgesl?（?double?a[]?int?lda?int?n?int?ipvt[]?double?b[]?int?job?）;
void?dscal?（?int?n?double?sa?double?x[]?int?incx?）;
int?idamax?（?int?n?double?dx[]?int?incx?）;
double?r8_abs?（?double?x?）;
double?r8_epsilon?（?void?）;
double?r8_max?（?double?x?double?y?）;
double?r8_random?（?int?iseed[4]?）;
double?*r8mat_gen?（?int?lda?int?n?）;
void?timestamp?（?void?）;

/******************************************************************************/

int?main?（?void?）

/******************************************************************************/
/*
??Purpose:

????MAIN?is?the?main?program?for?LINPACK_BENCH.

??Discussion:

????LINPACK_BENCH?drives?the?double?precision?LINPACK?benchmark?program.

??Modified:

????25?July?2008

??Parameters:

????N?is?the?problem?size.
*/
{
#?define?N?1000
#?define?LDA?（?N?+?1?）

??double?*a;
??double?a_max;
??double?*b;
??double?b_max;
??double?cray?=?0.056;
??double?eps;
??int?i;
??int?info;
??int?*ipvt;
??int?j;
??int?job;
??double?ops;
??double?*resid;
??double?resid_max;
??double?residn;
??double?*rhs;
??double?t1;
??double?t2;
??double?time[6];
??double?total;
??double?*x;

??timestamp?（?）;
??printf?（?“\n“?）;
??printf?（?“LINPACK_BENCH\n“?）;
??printf?（?“??C?version\n“?）;
??printf?（?“\n“?）;
??printf?（?“??The?LINPACK?benchmark.\n“?）;
??printf?（?“??Language:?C\n“?）;
??printf?（?“??Datatype:?Double?precision?real\n“?）;
??printf?（?“??Matrix?order?N???????????????=?%d\n“?N?）;
??printf?（?“??Leading?matrix?dimension?LDA?=?%d\n“?LDA?）;

??ops?=?（?double?）?（?2?*?N?*?N?*?N?）?/?3.0?+?2.0?*?（?double?）?（?N?*?N?）;
/*
??Allocate?space?for?arrays.
*/
??a?=?r8mat_gen?（?LDA?N?）;
??b?=?（?double?*?）?malloc?（?N?*?sizeof?（?double?）?）;
??ipvt?=?（?int?*?）?malloc?（?N?*?sizeof?（?int?）?）;
??resid?=?（?double?*?）?malloc?（?N?*?sizeof?（?double?）?）;
??rhs?=?（?double?*?）?malloc?（?N?*?sizeof?（?double?）?）;
??x?=?（?double?*?）?malloc?（?N?*?sizeof?（?double?）?）;

??a_max?=?0.0;
??for?（?j?=?0;?j???{
????for?（?i?=?0;?i?????{
??????a_max?=?r8_max?（?a_max?a[i+j*LDA]?）;
????}
??}

??for?（?i?=?0;?i???{
????x[i]?=?1.0;
??}

??for?（?i?=?0;?i???{
????b[i]?=?0.0;
????for?（?j?=?0;?j?????{
??????b[i]?=?b[i]?+?a[i+j*LDA]?*?x[j];
????}
??}
??t1?=?cpu_time?（?）;

??info?=?dgefa?（?a?LDA?N?ipvt?）;

??if?（?info?!=?0?）
??{
????printf?（?“\n“?）;
????printf?（?“LINPACK_BENCH?-?Fatal?error!\n“?）;
????printf?（?“??The?matrix?A?is?apparently?singular.\n“?）;
????printf?（?“??Abnormal?end?of?execution.\n“?）;
????return?1;
??}

??t2?=?cpu_time?（?）;
??time[0]?=?t2?-?t1;

??t1?=?cpu_time?（?）;

??job?=?0;
??dgesl?（?a?LDA?N?ipvt?b?job?）;

??t2?=?cpu_time?（?）;
??time[1]?=?t2?-?t1;

??total?=?time[0]?+