1038. Binary Search Tree to Greater Sum Tree
阿新 • • 發佈:2020-08-17
Given the root of a binarysearchtree with distinct values, modify it so that everynode
has a new value equal to the sum of the values of the original tree that are greater than or equal tonode.val
.
As a reminder, abinary search treeis a tree that satisfies these constraints:
- The left subtree of a node contains only nodes with keysless thanthe node's key.
- The right subtree of a node contains only nodes with keysgreater thanthe node's key.
- Both the left and right subtrees must also be binary search trees.
Example 1:
Input: [4,1,6,0,2,5,7,null,null,null,3,null,null,null,8]
Output: [30,36,21,36,35,26,15,null,null,null,33,null,null,null,8]
Constraints:
- The number of nodes in the tree is between
1
and100
. - Each node will have value between
0
and100
. - The given tree is a binary search tree.
class Solution { int sum = 0; public TreeNode convertBST(TreeNode root) { convert(root); return root; } public void convert(TreeNode root) {if(root == null) return; convert(root.right); root.val += sum; sum = root.val; convert(root.left); } }
wdnmd你知道和538一樣害po出來??