#!/usr/bin/perl -w 
 
use strict; 
 
my %data = ( 
            1 => 'foo', 
            3 => 'bar', 
            7 => 'baz', 
            12 => 'fumble' 
           ); 
 
print &find_nearest (10, \%data); 
 
sub find_nearest($\%) { 
  my $target = shift; 
  my %data = %{shift()}; 
  while (!defined $data{$target}) { 
    $target--; 
  } 
  return $target; 
}
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