#!/usr/bin/env perl

use Data::Dumper;


my $lastx = 4;
my $lasty = 5;

my $points = [];
for ( my $i1=0; $i1<=$lastx; $i1++ )
{
    for ( my $i2=0; $i2<=$lasty; $i2++)
    {
        push @$points, [$i2, $i1] ;
    }
}


my $position = {};
foreach my $letter (  ('a'.. 'z', 'A' .. 'Z' )[0.. scalar(@$points)-1]
+ )
{
    $position->{$letter} = pop(@$points);
}

foreach my $letter ( sort { "\L$a" cmp "\L$b"  } keys %$position )
{
    say "$letter = [ $position->{$letter}[0], $position->{$letter}[1] 
+]";
}
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bugger - just saw that poj beat me and with a much neater solution .. is cool that you can just inc a letter and it will expand from z -> aa .. didn't know that.