Don't pass in 0 as it will mess up the comparison

src/engine/mod.rs

@@ -152,7 +152,7 @@ impl Engine {
 
     fn search<F>(&mut self, game: &Game, stop: F) where F: Fn(usize, usize, usize) -> bool {
         self.send_new_state_to_workers(game);
-        let initial_playouts = self.root.playouts();
+        let initial_playouts = self.root.playouts() + 1; // Never pass in 0 below
         loop {
             let (playouts_best, playouts_second_best) = self.root.best2_playouts();
             let done = {