bug fix gcc build

src/solver/solver_result.cpp

@@ -3,7 +3,7 @@
 namespace DPF {
 
 	const std::vector<InternalNodeDescription> SolverResult::GetSolutionsInOrder() const {
-		std::vector<InternalNodeDescription> solutions(solutions->solutions.begin(), solutions->solutions.end());
+		std::vector<InternalNodeDescription> solutions(this->solutions->solutions.begin(), this->solutions->solutions.end());
 		std::sort(solutions.begin(), solutions.end(), [](const InternalNodeDescription& n1, const InternalNodeDescription& n2) {
 			return n1.GetPartialSolution().GetMisclassifications() < n2.GetPartialSolution().GetMisclassifications();
 		});