my $Str = "AAAA001BBBB001CCCC000DDDD023EEEE012";
my %H;

while($Str) {
    my $s = substr($Str, 0, 4, '');
    my $i = substr($Str, 0, 3, '');
    %H{$s} = $i;
    }
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Output:
AAAA -> 001
BBBB -> 001
CCCC -> 000
DDDD -> 023
EEEE -> 012
[download]