small corrections in CouplinIterationInterface

AMDiS/src/CouplingIterationInterface.cc

@@ -28,7 +28,7 @@ namespace AMDiS {
   /// add problem by number
   void CouplingIterationInterface::addIterationInterface(ProblemIterationInterface* probIter, int number)
   {
-    unsigned idx = std::min(problems.size(), static_cast<unsigned>(number)); 
+    size_t idx = std::min(problems.size(), static_cast<size_t>(number)); 
     if (number < 0)
       idx = problems.size();
     std::vector<ProblemIterationInterface*>::iterator pos = problems.begin() + idx;