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return 1 if (defined $_[0] && $_[0] =~ /^[\d\.]+$/ && $_[0] =~ /\d/ &&
+ ( () = $_[0] =~ /\./g ) <= 1);
return 1 if ( defined $_[0] && length($_[0]) == ($_[0] =~ tr/012345678
+9.//) && ( $_[0] =~ tr/0123456789//) >= 1 && ($_[0] =~ tr/.//) <= 1);