Try to make the correct solver into a local solver

As far as I can tell, it's worked! Hooray!

1 files changed, 4 insertions, 0 deletions

diff --git a/impl/IdSet.hpp b/impl/IdSet.hpp
index 950b1e1..bf98502 100644
--- a/impl/IdSet.hpp
+++ b/impl/IdSet.hpp
@@ -96,6 +96,10 @@ class IdSet {
     return _set.size();
   }
 
+  bool empty() const {
+    return _set.empty();
+  }
+
   private:
   unsigned int _range;
   std::set<unsigned int> _set;