data_structures.binary_tree.persistent_segment_tree =================================================== .. py:module:: data_structures.binary_tree.persistent_segment_tree Attributes ---------- .. autoapisummary:: data_structures.binary_tree.persistent_segment_tree.result Classes ------- .. autoapisummary:: data_structures.binary_tree.persistent_segment_tree.Node data_structures.binary_tree.persistent_segment_tree.PersistentSegmentTree Module Contents --------------- .. py:class:: Node .. py:attribute:: left :type: Node | None :value: None .. py:attribute:: right :type: Node | None :value: None .. py:attribute:: value :type: int .. py:class:: PersistentSegmentTree(arr: list[int]) .. py:method:: _build(arr: list[int], start: int, end: int) -> Node Builds a segment tree from the provided array. >>> pst = PersistentSegmentTree([1, 2, 3, 4]) >>> root = pst._build([1, 2, 3, 4], 0, 3) >>> root.value # Sum of the whole array 10 >>> root.left.value # Sum of the left half 3 >>> root.right.value # Sum of the right half 7 .. py:method:: _query(node: Node, start: int, end: int, left: int, right: int) -> int Queries the sum of values in the range [left, right] for the given node. >>> pst = PersistentSegmentTree([1, 2, 3, 4]) >>> root = pst.roots[0] >>> pst._query(root, 0, 3, 1, 2) # Sum of elements at index 1 and 2 5 >>> pst._query(root, 0, 3, 0, 3) # Sum of all elements 10 >>> pst._query(root, 0, 3, 2, 3) # Sum of elements at index 2 and 3 7 .. py:method:: _update(node: Node, start: int, end: int, index: int, value: int) -> Node Update the node for the specified index and value and return the new node. >>> pst = PersistentSegmentTree([1, 2, 3, 4]) >>> old_root = pst.roots[0] >>> new_root = pst._update(old_root, 0, 3, 1, 5) # Update index 1 to 5 >>> new_root.value # New sum after update 13 >>> old_root.value # Old root remains unchanged 10 >>> new_root.left.value # Updated left child 6 >>> new_root.right.value # Right child remains the same 7 .. py:method:: query(version: int, left: int, right: int) -> int Queries the sum in the given range for the specified version. >>> pst = PersistentSegmentTree([1, 2, 3, 4]) >>> pst.query(0, 0, 3) # Sum of all elements in original version 10 >>> pst.query(0, 1, 2) # Sum of elements at index 1 and 2 in original version 5 >>> version_1 = pst.update(0, 1, 5) # Update index 1 to 5 >>> pst.query(version_1, 0, 3) # Sum of all elements in new version 13 >>> pst.query(version_1, 1, 2) # Sum of elements at index 1 and 2 8 .. py:method:: update(version: int, index: int, value: int) -> int Updates the value at the given index and returns the new version. >>> pst = PersistentSegmentTree([1, 2, 3, 4]) >>> version_1 = pst.update(0, 1, 5) # Update index 1 to 5 >>> pst.query(version_1, 0, 3) # Query sum of all elements in new version 13 >>> pst.query(0, 0, 3) # Original version remains unchanged 10 >>> version_2 = pst.update(version_1, 3, 6) # Update index 3 to 6 in version_1 >>> pst.query(version_2, 0, 3) # Query sum of all elements in newest version 15 .. py:attribute:: n :type: int .. py:attribute:: roots :type: list[Node] :value: [] .. py:data:: result