use strict;
use warnings;
use utf8;
binmode STDIN, ':encoding(cp932)';
binmode STDOUT, ':encoding(cp932)';
binmode STDERR, ':encoding(cp932)';

&check("book is 2000yen, cake is 800yen");
&check("orange is 950yen");
&check("3500yen?");

sub check{
  my ($str) = @_;

  if ($str =~ /\d+yen/){
    print "<$`><$&><$'>\n";
  }
}