There are 18,900 volumes of science and technology books, literature and art books, and comic books in the library, including 6,780 volumes of science and technology books and 5,450 volumes of literature and art books. How many volumes of comic books are there?
图书室有科技书、文艺书、买连环画共18900册，其中科技书有6780册，文艺书有5450册，问连环画有多少册？
<gadget id="calculator">18_900 - 6_780 - 5_450</gadget>
<output>6_670</output>

<result>6_670</result>