123 lines
2.4 KiB
C++
123 lines
2.4 KiB
C++
|
/* BYTE magazine October 1982. Jerry Pournelle. */
|
||
|
|
/* ported to C by David Lee */
|
||
|
|
/* various bugs not found because dimensions are square fixed by David Lee */
|
||
|
|
/* expected result: 4.65880E+05 */
|
||
|
|
/* normal version runs in 13 seconds on the original PC and 8.9 seconds with the "f/fast" versions */
|
||
|
|
|
||
|
|
#define LINT_ARGS
|
||
|
|
|
||
|
|
#include <stdio.h>
|
||
|
|
|
||
|
|
#define l 20 /* rows in A and resulting matrix C */
|
||
|
|
#define m 20 /* columns in A and rows in B (must be identical) */
|
||
|
|
#define n 20 /* columns in B and resulting matrix C */
|
||
|
|
|
||
|
|
#define ftype float
|
||
|
|
|
||
|
|
ftype Summ;
|
||
|
|
ftype A[ l ] [ m ];
|
||
|
|
ftype B[ m ] [ n ];
|
||
|
|
ftype C[ l ] [ n ];
|
||
|
|
|
||
|
|
void filla()
|
||
|
|
{
|
||
|
|
register int i, j;
|
||
|
|
for ( i = 0; i < l; i++ )
|
||
|
|
for ( j = 0; j < m; j++ )
|
||
|
|
A[ i ][ j ] = i + j + 2;
|
||
|
|
}
|
||
|
|
|
||
|
|
void fillb()
|
||
|
|
{
|
||
|
|
register int i, j;
|
||
|
|
for ( i = 0; i < m; i++ )
|
||
|
|
for ( j = 0; j < n; j++ )
|
||
|
|
B[ i ][ j ] = (ftype) ( ( i + j + 2 ) / ( j + 1 ) );
|
||
|
|
}
|
||
|
|
|
||
|
|
void fillc()
|
||
|
|
{
|
||
|
|
register int i, j;
|
||
|
|
for ( i = 0; i < l; i++ )
|
||
|
|
for ( j = 0; j < n; j++ )
|
||
|
|
C[ i ][ j ] = 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
void ffillc()
|
||
|
|
{
|
||
|
|
ftype * p = (ftype *) C;
|
||
|
|
ftype * pend = ( (ftype *) C ) + ( l * n );
|
||
|
|
|
||
|
|
while ( p < pend )
|
||
|
|
*p++ = 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
void matmult()
|
||
|
|
{
|
||
|
|
register int i, j, k;
|
||
|
|
for ( i = 0; i < l; i++ )
|
||
|
|
for ( j = 0; j < n; j++ )
|
||
|
|
for ( k = 0; k < m; k++ )
|
||
|
|
C[ i ][ j ] += A[ i ][ k ] * B[ k ][ j ];
|
||
|
|
}
|
||
|
|
|
||
|
|
void fmatmult()
|
||
|
|
{
|
||
|
|
static int i, j, k;
|
||
|
|
static ftype * pC, * pA, * pAI, * pBJ, *pCI;
|
||
|
|
|
||
|
|
for ( i = 0; i < l; i++ )
|
||
|
|
{
|
||
|
|
pAI = (ftype *) & ( A[ i ][ 0 ] );
|
||
|
|
pCI = (ftype *) & ( C[ i ][ 0 ] );
|
||
|
|
|
||
|
|
for ( j = 0; j < n; j++ )
|
||
|
|
{
|
||
|
|
pC = (ftype *) & pCI[ j ];
|
||
|
|
pA = pAI;
|
||
|
|
pBJ = & ( B[ 0 ][ j ] );
|
||
|
|
|
||
|
|
for ( k = 0; k < m; k++ )
|
||
|
|
{
|
||
|
|
*pC += pA[ k ] * ( *pBJ );
|
||
|
|
pBJ += m;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void summit()
|
||
|
|
{
|
||
|
|
register int i, j;
|
||
|
|
for ( i = 0; i < l; i++ )
|
||
|
|
for ( j = 0; j < n; j++ )
|
||
|
|
Summ += C[ i ][ j ];
|
||
|
|
}
|
||
|
|
|
||
|
|
void fsummit()
|
||
|
|
{
|
||
|
|
ftype * p = (ftype *) C;
|
||
|
|
ftype * pend = ( (ftype *) C ) + ( l * n );
|
||
|
|
|
||
|
|
while ( p < pend )
|
||
|
|
Summ += *p++;
|
||
|
|
}
|
||
|
|
|
||
|
|
int main( argc, argv ) int argc; char * argv[];
|
||
|
|
{
|
||
|
|
Summ = 0;
|
||
|
|
|
||
|
|
filla();
|
||
|
|
fillb();
|
||
|
|
ffillc();
|
||
|
|
|
||
|
|
fmatmult();
|
||
|
|
fsummit();
|
||
|
|
|
||
|
|
printf( "summ is : %f\n", Summ );
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
|