diff --git a/xs/src/clipper.cpp b/xs/src/clipper.cpp
index f3740f9d1..83153c996 100644
--- a/xs/src/clipper.cpp
+++ b/xs/src/clipper.cpp
@@ -2588,7 +2588,7 @@ void Clipper::ProcessHorizontal(TEdge *horzEdge)
 
   MaximaList::const_iterator maxIt;
   MaximaList::const_reverse_iterator maxRit;
-  if (m_Maxima.size() > 0)
+  if (!m_Maxima.empty())
   {
       //get the first maxima in range (X) ...
       if (dir == dLeftToRight)
@@ -2620,7 +2620,7 @@ void Clipper::ProcessHorizontal(TEdge *horzEdge)
         //this code block inserts extra coords into horizontal edges (in output
         //polygons) whereever maxima touch these horizontal edges. This helps
         //'simplifying' polygons (ie if the Simplify property is set).
-        if (m_Maxima.size() > 0)
+        if (!m_Maxima.empty())
         {
             if (dir == dLeftToRight)
             {