Pathologically Eclectic Rubbish Lister PerlMonks

### Re: Problem creating array

by Unforgiven (Hermit)
 on Sep 16, 2009 at 14:26 UTC ( #795629=note: print w/replies, xml ) Need Help??

in reply to Problem creating array

I just used a foreach, because the x looked to be related to the problem, and it was the first and simplest thing that came to mind. You could do it shorter and more elegantly, but this works and is probably a little easier to read if you're still learning a bit.
```my @count = (1,3,1,1,1,1,1,2,1,1,3,2);
my @result;

for (my \$i=0; \$i <= \$#count; \$i++) {
foreach (1 .. \$count[\$i]) {
push(@result, \$i);
}
}

print "\@count: @count\n";
print "\@result: @result\n";

Replies are listed 'Best First'.
Re^2: Problem creating array
by AnomalousMonk (Bishop) on Sep 16, 2009 at 16:56 UTC
The shorter, more elegant approach involves the use of the map built-in. You (Subop) don't need it right now, but you should keep  map in mind as you build your Perl skills.
```>perl -wMstrict -le
"my @count  = (1, 3, 1, 1, 1, 1, 1, 2, 1, 1, 3, 2);
my @result = map { (\$_) x \$count[\$_] } 0 .. \$#count;
print qq{@count};
print qq{@result};
"
1 3 1 1 1 1 1 2 1 1 3 2
0 1 1 1 2 3 4 5 6 7 7 8 9 10 10 10 11 11

A slightly simpler map at the cost of declaring another scalar.

```\$ perl -Mstrict -wle '
> my @count = ( 1, 3, 1, 1, 1, 1, 1, 2, 1, 1, 3, 2 );
> my \$idx;
> my @result = map { ( \$idx ++ ) x \$_ } @count;
> print qq{@count};
> print qq{@result};'
1 3 1 1 1 1 1 2 1 1 3 2
0 1 1 1 2 3 4 5 6 7 7 8 9 10 10 10 11 11
\$

I hope this is of interest.

Cheers,

JohnGG

Create A New User
Node Status?
node history
Node Type: note [id://795629]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others lurking in the Monastery: (2)
As of 2020-10-22 07:12 GMT
Sections?
Information?
Find Nodes?
Leftovers?
Voting Booth?
My favourite web site is:

Results (225 votes). Check out past polls.

Notices?