Question regarding the FOR loop

[TheGenius22]

Hello All,

Hope your enjoying your day so far.

It's a really simple question.

For the FOR loop, I would like for it to count backwards.

EX:

for (1 .. 5)
{
print "$_\n";
}

it prints
1
2
3
4
5

I would like for it to print this way

5
4
3
2
1

I already have a work around by inserting an extra variable.

But I would like to know if the loop itslef can count backwards.

Something like :

reverse(for( 1.. 5))
{
print "$_\n";
}

Thanks,

 

[bardley]

well, you can do

for (reverse(1..5)) {
print "$_\n";
}

but I wouldn't do it for huge numbers of iterations.

That code actually creates the list (1, 2, 3, 4, 5), reverses it, then does the loop for each member of the list. Creating a long array is a bad idea; creating a long array and reversing it is a REALLY bad idea. Quicker to use a counter.


Brad Gunsalus
bardley90@hotmail.com

 

[Stiddy]

here a bit that may help you:

my $count;
$| = 1;
for ($count = 300; $count >= 0; $count--){
printf("%3d",$count);
sleep 1;
print((chr 8)x3);
}

 

[duncdude]

#!/usr/bin/perl

for ($x=5; $x>=1; $x--)
{
  print "$x\n";
}

Kind Regards
Duncan

 

[iribach]

yes duncdude,
this guy cannot think, not logic
but is
$x>=1
not the same as(4 readability ++ assumed
$x is a positive value)
$x >0
?

 

[duncdude]

yes... wasn't really applying myself


Kind Regards
Duncan

 

[duncdude]

Hi TheGenius22

I really don't want to appear rude but you might want to get hold of a nice & simple book on learning Perl e.g. Perl in Easy Steps

A book like this will take you through all of the common Perl functions - without the heavier stuff. You'll get through it in no time as the suggestion you posted is more involved - therefore the examples will be a breeze for you. You can only have come at this problem from an awkward angle. Give it a shot.

As I said - I really do not intend this message to appear rude!


Kind Regards
Duncan