X-Git-Url: http://git.nguyen.vg/gitweb/?a=blobdiff_plain;f=XMLTree.cpp;h=21658e99c323c4aaaff8b72e385d8580542bddf4;hb=d1f17224ed40165c284145ffbfcc1bd42882f825;hp=92360a432535065f46769245eadee9f98515c005;hpb=a9846746dc7a55764591fcc273fd48c6049df962;p=SXSI%2FXMLTree.git

diff --git a/XMLTree.cpp b/XMLTree.cpp
index 92360a4..21658e9 100644
--- a/XMLTree.cpp
+++ b/XMLTree.cpp
@@ -311,8 +311,10 @@ treeNode XMLTree::Parent(treeNode x)
        fprintf(stderr, "Error: data structure has not been constructed properly\n");
        exit(1);
     }
-
-    return parent(Par, x);
+    if (x == Root())
+      return NULLT;
+    else
+      return parent(Par, x);
  }
 
 // Child(x,i): returns the i-th child of node x, assuming it exists.
@@ -345,7 +347,9 @@ treeNode XMLTree::NextSibling(treeNode x)
        fprintf(stderr, "Error: data structure has not been constructed properly\n");
        exit(1);
     }
-
+    if (x == Root())
+      return NULLT;
+ 
     return next_sibling(Par, x);
  }