You probably want to store them in a hash of arrays. Untested code: 
my %Data;
while(<DATA>)
{
  my ( $City, $Value ) = split;
  push ( @{$Data{ $City }}, $Value );
}
__DATA__
amsterdam   23
amsterdam   88
london      65
ny          10
ny          16
la          21
la          65 
miami        9 
lapaz       10

[download]
That should give you 
(
  amsterdam => [23, 88],
  london => [65],
  ny => [10, 16],
  la => [21, 65],
  miami => [9],
  lapaz => [10]
)

[download]

--t. alex
but my friends call me T.

In reply to Re: arrays or hashes by talexb
in thread arrays or hashes by Anonymous Monk

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