Switch to side-by-side view

--- a/src/query/docseqhist.cpp
+++ b/src/query/docseqhist.cpp
@@ -17,6 +17,7 @@
  *   Free Software Foundation, Inc.,
  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  */
+#include <stdio.h>
 #include <math.h>
 #include <time.h>
 #include <cmath>