Merge pull request #40 from ProgVal/begin-end-complexity

Complexity of IntervalTree.{begin,end} is O(1), not O(n).

Author: chaimleib

intervaltree/intervaltree.py

@@ -818,7 +818,7 @@ def begin(self):
         """
         Returns the lower bound of the first interval in the tree.
         
-        Completes in O(n) time.
+        Completes in O(1) time.
         """
         if not self.boundary_table:
             return 0
@@ -828,7 +828,7 @@ def end(self):
         """
         Returns the upper bound of the last interval in the tree.
         
-        Completes in O(n) time.
+        Completes in O(1) time.
         """
         if not self.boundary_table:
             return 0