diff --git a/gamedata.cpp b/gamedata.cpp
index 3af9f37..6474bac 100644
--- a/gamedata.cpp
+++ b/gamedata.cpp
@@ -93,7 +93,7 @@ bool GameData::add_vertex(int x, int y, int r, int colour)
 	{
 	    Graph::add_vertex(x, y, r, colour, 10);
 #ifdef DEBUG
-	fprintf(stderr, "debug: GameData::add_vertex(): strength=%f\n",
+	fprintf(stderr, "debug: GameData::add_vertex(): strength=%2.f\n",
 		calculate_strength(*(vertices.rbegin())));
 #endif
 	    if (player == PLAYER1) player1_played = true;
@@ -107,7 +107,7 @@ bool GameData::add_vertex(int x, int y, int r, int colour)
     if (Graph::add_vertex(x, y, r, colour, 10, current))
     {
 #ifdef DEBUG
-	fprintf(stderr, "debug: GameData::add_vertex(): strength=%f\n",
+	fprintf(stderr, "debug: GameData::add_vertex(): strength=%.2f\n",
 		calculate_strength(*(vertices.rbegin())));
 #endif
 
@@ -192,6 +192,8 @@ int GameData::get_range(Vertex* node)
 	    Vertex* v = *cursor;
 	    range -= 100 - MathUtils::distance(v->x, v->y, node->x, node->y);
 	}
+	if (range < 0) range = 0;
+	return range;
     }
 }
 
@@ -209,7 +211,7 @@ void GameData::attack_vertex(Vertex* target)
     if (target->score <= 0) remove_vertex(target);
 
 #ifdef DEBUG
-    fprintf(stderr, "debug: GameData::attack_vertex(): atk_str=%2.f, def_str=%2.f, armor=%2.f, damage=%d\n", atk_str, def_str, armor, damage);
+    fprintf(stderr, "debug: GameData::attack_vertex(): atk_str=%.2f, def_str=%.2f, armor=%.2f, damage=%d\n", atk_str, def_str, armor, damage);
 #endif
 
     toggle_turn();