Wow, that's a lot of excessive work; why use the hash, when a regex can count matches? 

my @keep;
while ( chomp(my $num = <DATA>) ) {
   for ( split //, $num ) {
      my @a = ($num =~ m/$_/g);             #count occurances
      if (@a>1) { push @keep, $num; last; } #keep if more than one
   }
}

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<-radiant.matrix->
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In reply to Re^2: Find duplicate digits by radiantmatrix
in thread Find duplicate digits by Anonymous Monk

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