TODO: modify other races constructors

did some reworking

src/position.cc

@@ -65,16 +65,12 @@ std::vector<position> remove_from_list(const std::vector<position>
         return result;
 }
 
-std::vector<position> remove_from_list(const std::vector<position>
-                                       &sorted_positions,
-                                       position &excluded) {
-
-        std::vector<position> result{sorted_positions.size() - 1};
-
-        for (auto src : sorted_positions) {
-                if (src != excluded)
-                        result.push_back(src);
-        }
-
-        return result;
+void remove_from_list(std::vector<position>
+                      &positions,
+                      position &excluded) {
+        for (auto i = positions.begin(); i != positions.end(); ++i)
+                if (*i == excluded) {
+                        positions.erase(i);
+                        return;
+                }
 }