Small rework of optimal vs maxsols

I wanted to make the "optimal" and "maxsolutions" options mutually
exclusive, but in the end I decided there is value in keeping both
(e.g. for specifying a limit to the number of solutions when asking
for "all" optimal").

Now optimal cannot be negative anymore, for the same reason of maxsolutions.

The interface user (shell, UI) will have to take care of handling this
in a way that makes sense for the user. Usually this means setting
the maximum number of solutions to UINT_MAX (or a similar very high
number) when the user wants "all optimal".

1 files changed, 2 insertions, 2 deletions

diff --git a/cpp/nissy.h b/cpp/nissy.h
index db8ba5f..4b9c1c9 100644
--- a/cpp/nissy.h
+++ b/cpp/nissy.h
@@ -91,8 +91,8 @@ namespace nissy {
                 error check_data();
                 void unload_data();
                 solve_result solve(const cube&, nissflag, unsigned minmoves,
-                    unsigned maxmoves, unsigned maxsols, int optimal,
-                    int threads);
+                    unsigned maxmoves, unsigned maxsols, unsigned optimal,
+                    unsigned threads);
 
                 static std::variant<solver, error> get(const std::string&);
         private: