diff --git a/LibCarla/source/carla/trafficmanager/LocalizationStage.cpp b/LibCarla/source/carla/trafficmanager/LocalizationStage.cpp
index e4f893246..3c2ebca42 100644
--- a/LibCarla/source/carla/trafficmanager/LocalizationStage.cpp
+++ b/LibCarla/source/carla/trafficmanager/LocalizationStage.cpp
@@ -119,8 +119,8 @@ namespace LocalizationConstants {
           for (auto swp: waypoint_buffer) {
             RemoveOverlap(swp->GetId(), actor_id);
           }
-          uint number_of_pops = waypoint_buffer.size();
-          for (uint i = 0; i < number_of_pops; ++i) {
+          auto number_of_pops = waypoint_buffer.size();
+          for (uint j = 0; j < number_of_pops; ++j) {
             PopWaypoint(waypoint_buffer, actor_id);
           }
 
diff --git a/LibCarla/source/carla/trafficmanager/TrafficManager.cpp b/LibCarla/source/carla/trafficmanager/TrafficManager.cpp
index 783f51b5f..7173e0ef8 100644
--- a/LibCarla/source/carla/trafficmanager/TrafficManager.cpp
+++ b/LibCarla/source/carla/trafficmanager/TrafficManager.cpp
@@ -177,8 +177,8 @@ namespace traffic_manager {
     }
   }
 
-  bool TrafficManager::CheckAllFrozen(std::vector<cc::TrafficLight> tl_to_freeze) {
-    for (auto elem : tl_to_freeze) {
+  bool TrafficManager::CheckAllFrozen(TLGroup tl_to_freeze) {
+    for (auto& elem : tl_to_freeze) {
       if (!elem->IsFrozen() or elem->GetState() != TLS::Red) {
         return false;
       }
@@ -188,34 +188,34 @@ namespace traffic_manager {
 
   void TrafficManager::ResetAllTrafficLights() {
     auto world_traffic_lights = world.GetActors()->Filter("*traffic_light*");
-
-    std::vector<std::vector<cc::TrafficLight>> list_of_all_groups;
-    std::vector<cc::TrafficLight> tl_to_freeze;
+    std::vector<TLGroup> list_of_all_groups;
+    TLGroup tl_to_freeze;
     std::vector<carla::ActorId> list_of_ids;
 
     for (auto tl : *world_traffic_lights.get()) {
-        if (std::find(list_of_ids.begin(), list_of_ids.end(), tl->GetId()) != list_of_ids.end()) {
-            auto tl_group = boost::static_pointer_cast<cc::TrafficLight>(tl)->GetGroupTrafficLights();
-            list_of_all_groups.push_back(tl_group.at(0).get());
-            // tl_group is a std::vector<boost::shared_ptr<carla::client::TrafficLight>
-            for (unsigned i=0; i<tl_group.size(); i++) {
-                // tlg is a boost::shared_ptr<carla::client::TrafficLight>
-                // tlg->Id is a carla::ActorId
-                list_of_ids.push_back(tl_group.at(i).get()->GetId());
-                if(i!=0) {
-                    tl_to_freeze.push_back(tl_group.at(i).get());
-                }
+      if (std::find(list_of_ids.begin(), list_of_ids.end(), tl->GetId()) != list_of_ids.end()) {
+          TLGroup tl_group = boost::static_pointer_cast<cc::TrafficLight>(tl)->GetGroupTrafficLights();
+          list_of_all_groups.push_back(tl_group);
+          // tl_group is a std::vector<boost::shared_ptr<carla::client::TrafficLight>
+          for (unsigned i=0; i<tl_group.size(); i++) {
+              // tlg is a boost::shared_ptr<carla::client::TrafficLight>
+              // tlg->Id is a carla::ActorId
+              list_of_ids.push_back(tl_group.at(i).get()->GetId());
+              if(i!=0) {
+                  tl_to_freeze.push_back(tl_group.at(i));
               }
-          }
-      }
-    for (auto &tl_group : list_of_all_groups) {
-      tl_group.begin()->SetState(TLS::Green);
-      for (auto tl = std::next(tl_group.begin(),1); tl != tl_group.end(); ++tl) {
-        tl->SetState(TLS::Red);
+            }
+        }
       }
+
+    for (TLGroup& tl_group : list_of_all_groups) {
+      tl_group.front()->SetState(TLS::Green);
+      std::for_each(tl_group.begin() +1, tl_group.end(),
+                    [] (auto& tl) {tl->SetState(TLS::Red);});
     }
+
     while (!CheckAllFrozen(tl_to_freeze)) {
-      for (auto tln : tl_to_freeze) {
+      for (auto& tln : tl_to_freeze) {
           tln->SetState(TLS::Red);
           tln->Freeze(true);
       }
diff --git a/LibCarla/source/carla/trafficmanager/TrafficManager.h b/LibCarla/source/carla/trafficmanager/TrafficManager.h
index 516293d4e..d2f839e71 100644
--- a/LibCarla/source/carla/trafficmanager/TrafficManager.h
+++ b/LibCarla/source/carla/trafficmanager/TrafficManager.h
@@ -31,6 +31,7 @@ namespace cc = carla::client;
 
   using ActorPtr = carla::SharedPtr<cc::Actor>;
   using TLS = carla::rpc::TrafficLightState;
+  using TLGroup = std::vector<carla::SharedPtr<cc::TrafficLight>>;
 
   /// The function of this class is to integrate all the various stages of
   /// the traffic manager appropriately using messengers.
@@ -120,7 +121,7 @@ namespace cc = carla::client;
     void SetDistanceToLeadingVehicle(const ActorPtr &actor, const float distance);
 
     /// Method to check if traffic lights are frozen.
-    bool CheckAllFrozen(std::vector<cc::TrafficLight> tl_to_freeze);
+    bool CheckAllFrozen(TLGroup tl_to_freeze);
 
     /// Method to reset all traffic lights.
     void ResetAllTrafficLights();