in reply to Next unused sequential number

Do you mean that if your array contained:

1001,1002,1003,1004,1006,1007,1009,1010

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You want a function to inspect the array and return 1005?

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

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Re^2: Next unused sequential number
by Anonymous Monk on Aug 05, 2011 at 17:17 UTC
    Exactly.
[reply]

      Unless your array of numbers is huge, I'd use a simple linear search: 

      sub first { 
    my $aref = shift; 
    $aref->[ $_ ]+1 != $aref->[ $_+1 ] 
        and return $aref->[ $_ ]+1 
        for 0 .. $#$aref-1; 
};;

@a = 1000..1100;;
splice @a, rand(100), 1 for 1 .. 10;;

print @a;;
1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 
+1014 1015 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028
+ ...

print first( \@a );;
1016

      [download]
      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]
[d/l]

      Exactly? The array contains 1001, 1002, 1003? Or the array has indexes 1001, 1002, 1003?

      For example:

      use strict;
use warnings;
use List::MoreUtils qw/firstidx/;

@array = qw/ fred tom jenny jeff claire /;
$array[3] = undef;
my $available_index = firstidx { not defined $_ } @array; 
$array[$available_index] = 'peter';
print "@array\n";
__END__
fred tom jenny peter claire

      [download]

      Dave

[reply]
[d/l]

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