// Download likeinterference.cql
// PGN output when run on sample.pgn

/*Theme by Steffen Slumstrup Nielsen.

The white queen T1 checks. A black rook or bishop T2 interposes along
the same line, itself attacking the black king. Then a white rook or
bishop T3 interposes again along the same line, giving check. At the
end, thus, the three thematic pieces and the black king are arranged
in a single line.*/

cql(input hhdbvi.pgn)
T1          //checking queen
 T2        //black interposing piece
   T3      //white final checker
      T1 T1
      T2 T2
      T3 T3