diff --git a/DataFormats/PatCandidates/src/PackedCandidate.cc b/DataFormats/PatCandidates/src/PackedCandidate.cc
index d25a2c4e6d6e4..3669c6bcc7efe 100644
--- a/DataFormats/PatCandidates/src/PackedCandidate.cc
+++ b/DataFormats/PatCandidates/src/PackedCandidate.cc
@@ -299,11 +299,11 @@ bool pat::PackedCandidate::overlap( const reco::Candidate & o ) const {
 }
 
 const reco::Candidate * pat::PackedCandidate::daughter( size_type ) const {
-  return 0;
+  return nullptr;
 }
 
 const reco::Candidate * pat::PackedCandidate::mother( size_type ) const {
-  return 0;
+  return nullptr;
 }
 
 const reco::Candidate * pat::PackedCandidate::daughter(const std::string&) const {
@@ -321,7 +321,7 @@ reco::Candidate * pat::PackedCandidate::daughter(const std::string&) {
 
 
 reco::Candidate * pat::PackedCandidate::daughter( size_type ) {
-  return 0;
+  return nullptr;
 }
 
 double pat::PackedCandidate::vertexChi2() const {
diff --git a/RecoEgamma/PhotonIdentification/plugins/PhotonIDValueMapProducer.cc b/RecoEgamma/PhotonIdentification/plugins/PhotonIDValueMapProducer.cc
index ca449a0b4c6ae..a17ad9cab6bd5 100644
--- a/RecoEgamma/PhotonIdentification/plugins/PhotonIDValueMapProducer.cc
+++ b/RecoEgamma/PhotonIdentification/plugins/PhotonIDValueMapProducer.cc
@@ -42,13 +42,13 @@ class PhotonIDValueMapProducer : public edm::stream::EDProducer<> {
   public:
   
   explicit PhotonIDValueMapProducer(const edm::ParameterSet&);
-  ~PhotonIDValueMapProducer();
+  ~PhotonIDValueMapProducer() override;
   
   static void fillDescriptions(edm::ConfigurationDescriptions& descriptions);
 
   private:
   
-  virtual void produce(edm::Event&, const edm::EventSetup&) override;
+  void produce(edm::Event&, const edm::EventSetup&) override;
 
   void writeValueMap(edm::Event &iEvent,
 		     const edm::Handle<edm::View<reco::Photon> > & handle,
@@ -269,7 +269,7 @@ void PhotonIDValueMapProducer::produce(edm::Event& iEvent, const edm::EventSetup
   if( !pfCandidatesHandle.isValid() )
     iEvent.getByToken(pfCandidatesTokenMiniAOD_, pfCandidatesHandle);
 
-  if( !isAOD && src->size() ) {
+  if( !isAOD && !src->empty() ) {
     edm::Ptr<pat::Photon> test(src->ptrAt(0));
     if( test.isNull() || !test.isAvailable() ) {
       throw cms::Exception("InvalidConfiguration")
@@ -519,7 +519,7 @@ ::computeWorstPFChargedIsolation(const T& photon, const U& pfCandidates,
     allIsolations.push_back(sum);
   }
 
-  if( allIsolations.size()>0 )
+  if( !allIsolations.empty() )
     worstIsolation = * std::max_element( allIsolations.begin(), allIsolations.end() );
   
   return worstIsolation;