Here's your program modified to work with use strict:

#!/usr/bin/perl
use strict;
use warnings;

my $input_data = << 'REPORT_OF_INPUT';
Bet01;;Bet05;;Bet06;;Bet12;;
230;238;101;103;138;146;112;116;;
230;238;101;103;146;146;108;112;;
224;238;0;0;146;146;110;118;;
238;238;0;0;146;146;112;114;;
REPORT_OF_INPUT

my @inputs = split "\n", $input_data;

my $line = shift @inputs;
$line =~ s/;;/;/g;
my @loci_codes = split ";", $line;

my %LOCI;

foreach my $line ( @inputs )
{
    my @alelos = split ";", $line;
    foreach my $locus ( @loci_codes )
    {
        my $allele1 = shift @alelos;
        my $allele2 = shift @alelos;
        $LOCI{$locus}{$allele1} += 1;
        $LOCI{$locus}{$allele2} += 1;
    }
}

foreach my $locus ( @loci_codes )
{
    foreach my $key ( keys ( %{$LOCI{$locus}} ) )
    {
        print "$locus ", $key, " = ", $LOCI{$locus}{$key}, "\n";
    }
}

[download]

Is that so hard?

perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

In reply to Re^3: variable as hash name by tobyink
in thread variable as hash name by blackzero

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.