Re: question on Arrays

[BioLion]

Maybe better to use a hash if you are going to check existence?

use strict;
use warnings;

## buffering off
++$|;

## for storing numbers entered so far
my %hsh;

while (1){
    print "Enter something (or nothing if you are bored):\n";
    ## get input
    my $num = <>;
    chomp $num;
    ## exit infinite loop if the user hits enter twice
    last if (!defined$num || $num eq '');
    
    ## check against previous input
    if (exists $hsh{$num}){
        print "Seen >$num< before, try again.\n";
        next; 
    }
    else {
        print "Oooh >$num< is new, thanks!\n";
        ++$hsh{$num};
    }
}

print +(join "\n\t", "Finished! You entered :", sort keys %hsh);

Sample terminal:

Enter something (or nothing if you are bored):
4
Oooh >4< is new, thanks!
Enter something (or nothing if you are bored):
foo
Oooh >foo< is new, thanks!
Enter something (or nothing if you are bored):
bar
Oooh >bar< is new, thanks!
Enter something (or nothing if you are bored):
4
Seen >4< before, try again.
Enter something (or nothing if you are bored):

Finished! You entered :
    4
    bar
    foo