FIX: fixed segmentation fault when deleting all children

src/Tree/tree.cpp

@@ -18,6 +18,7 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 #include <iostream>
 #include <iomanip>
 #include <Tree/tree.hpp>
+#include <iterator>
 #include <memory>
 
 std::list<std::shared_ptr<Tree::BaseNode>>::const_iterator Tree::BaseNode::getChildIterator(const std::shared_ptr<const Tree::BaseNode> child) const
@@ -132,7 +133,10 @@ void Tree::BaseNode::deleteChildren()
     {
       if ((*it) != nullptr )
       {
+        auto prev = std::prev(it);
         deleteChild((*it));
+        it=prev;
+        
       }
     }