#!/usr/bin/perl

use strict;
use warnings;

#------------ Declare hashes --------------------------
#
#  Array to contain the mapping from the input record to the output
#  record. The array index are the input record's field numbers, i (fr
+om
#  to n-1 where n are the number of fields;
#  the array value at the corresponding index is the output records,
#  field number, j.
#
my @from_to = (4,2,1,3);
   # convert index values into values from 0 to n-1
   my $len_array = scalar @from_to;
   for(my $i = 0; $i<$len_array; $i++){$from_to[$i]--};

#
#  Array to determine number of characters in each field.  The array i
+ndices
#  are the field number and the array values are the number of charact
+ers
#  in that field. As with @from_to, this array's indices go from 0 to 
+n-1
#  where n is the number of fields.
#
my @field_len = (10,4,6,6);

#------ Construct the decode string --------------------------
my $decode_str;
foreach my $len (@field_len){$decode_str .= 'A'.$len.' '};

#--------- Process each Input Record -------------------------
foreach my $record (<DATA>)
   {
   chomp($record);
   $record = join "",(unpack $decode_str,$record)[@from_to];
   print $record . "\n";
   }
   
   
   
exit(0);

__END__
AAAAAAAAAA1111BBBBBB222222
BBBBBBBBBB2222CCCCCC333333
CCCCCCCCCC3333DDDDDD444444
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