#!/usr/local/bin/perl for ($i=0; $i<256; $i++) { for ($j=0; $j<256; $j++) { $a0=$i&0x0f; $a1=($i>>4)&0x0f; $b0=$j&0x0f; $b1=($j>>4)&0x0f; $a0b0=$a0*$b0; $a1b1=$a1*$b1; $a01=$a0-$a1; $b10=$b1-$b0; $a01b10=$a01*$b10; if ($a01b10 < 0) { $neg=1; $a01b10= -$a01b10; } $t=($a0b0>>4)+($a0b0&0x0f)+($a1b1&0x0f); if ($neg) { $t-=($a01b10&0x0f); } else { $t+=($a01b10&0x0f); } printf("%02X %s%02X %02X\n",$a1b1,($neg)?"-":" ",$a01b10,$a0b0) if ($t < 0) } }