diff --git a/build.py b/build.py
index b68ad5d4b15c52acba9bf1a82a70bad0238e215e..7b933fb5c2416d5aafa2909062c3d1ced99f11e1 100644
--- a/build.py
+++ b/build.py
@@ -44,4 +44,4 @@ if __name__ == '__main__':
                 labout.write(plab.encode('utf8'))
                 labout.write(footer_bin)
 
-            os.system(('pandoc %s%s.md -s -o %s%s.pdf') % (dist_lp, ex_no, dist_lp, ex_no))
+            os.system(('pandoc %s/%s.md -s -o %s%s.pdf') % (dist_lp, ex_no, dist_lp, ex_no))