Dear Monks,

I am having trouble understanding a part of program that I am trying to tweak that I got off the web for sequence alignment.

I haven't changed anything but keep getting errors for 

while (scalar(@ra) 
while (scalar(@rb) 
while (scalar(@rc) # print out the answer

[download]

It is in the context of 

if (!$d->[$x][$y][0] && !$d->[$x][$y][1] && !$d->[$x][$y][2]) { 

            for (my $u=$x; $u>0; $u--) { unshift @ra, $sa[$u-1]; } 

            for (my $v=$y; $v>0; $v--) { unshift @rb, $sb[$v-1]; } 

                                while (scalar(@ra) 
                                while (scalar(@rb) 
                                while (scalar(@rc) # print out the ans
+wer 

                                $i++; # global variable 

                                $scr = 0; # score for each alignment 

                                print "<br>Alignment: $i<br>Sa:"; 

                                foreach my $x (@ra) { print "   $x"; }
+ 

                                print "<br>Sb:"; 

                                foreach my $y (@rb) { print "   $y"; }
+ 

                                print "<br>Scr"; 

                                foreach my $z (@rc) { 

                                if ($z eq '.') { 

                                            print "   ."; 

                                } else { 

                                            printf '%4d', $z; 
                                            
                                            $scr += $z; 
                                
                                }
                                
                        }

                        print " = $scr<br>"; 
                        
    }

[download]

What does it mean? And why do I keep getting errors? #I know that scalar() is to force scalar context.#

Thanks Monks, chris

In reply to while (scalar() by Anonymous Monk

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