Leetcode
2020.05.01 20:17

783. Minimum Distance Between BST Nodes

조회 수 442 추천 수 0 댓글 0
?

단축키

Prev이전 문서

Next다음 문서

크게 작게 위로 아래로 댓글로 가기 인쇄
?

단축키

Prev이전 문서

Next다음 문서

크게 작게 위로 아래로 댓글로 가기 인쇄

Given a Binary Search Tree (BST) with the root node root, return the minimum difference between the values of any two different nodes in the tree.

Example :

Input: root = [4,2,6,1,3,null,null]
Output: 1
Explanation:
Note that root is a TreeNode object, not an array.

The given tree [4,2,6,1,3,null,null] is represented by the following diagram:

          4
        /   \
      2      6
     / \    
    1   3  

while the minimum difference in this tree is 1, it occurs between node 1 and node 2, also between node 3 and node 2.

Note:

  1. The size of the BST will be between 2 and 100.
  2. The BST is always valid, each node's value is an integer, and each node's value is different.
  3. This question is the same as 530: https://leetcode.com/problems/minimum-absolute-difference-in-bst/


/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */
class Solution {
    public int minDiffInBST(TreeNode root) {
        Queue<TreeNode> queue = new LinkedList<>();
        List<Integer> list = new ArrayList<>();
        
        queue.offer(root);
        while(queue.size() > 0){
            int size = queue.size();
            for(int i=0; i<size; i++){
                TreeNode node = queue.poll();
                if(node.left != null){
                    queue.offer(node.left);
                }
                if(node.right != null){
                    queue.offer(node.right);
                }
                
                list.add(node.val);
            }
            
        }
        
        Collections.sort(list);
        
        int minDiff = Integer.MAX_VALUE;
        int prev = list.get(0);
        for(int i=1; i<list.size(); i++){
            int tmpDiff = Math.abs(prev - list.get(i));
            if(tmpDiff < minDiff){
                minDiff = tmpDiff;
            }
            prev = list.get(i);
        }
        
        return minDiff;
    }
}

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */
class Solution {
    public int minDiffInBST(TreeNode root) {
        Queue<TreeNode> queue = new LinkedList<>();
        List<Integer> list = new ArrayList<>();
        
        traverseBST(root, list);
        
        int minDiff = Integer.MAX_VALUE;
        int prev = list.get(0);
        for(int i=1; i<list.size(); i++){
            int tmpDiff = Math.abs(prev - list.get(i));
            if(tmpDiff < minDiff){
                minDiff = tmpDiff;
            }
            prev = list.get(i);
        }
        
        return minDiff;
    }
    
    public void traverseBST(TreeNode node, List<Integer> list){
        if(node == null){
            return;
        }
        
        traverseBST(node.left, list);
        list.add(node.val);
        traverseBST(node.right, list);
    }
}

[문제] https://leetcode.com/problems/minimum-distance-between-bst-nodes/



?

  1. 720. Longest Word in Dictionary

  2. 225. Implement Stack using Queues

  3. 56. Merge Intervals

  4. 844. Backspace String Compare

  5. 222. Count Complete Tree Nodes

  6. 697. Degree of an Array

  7. 605. Can Place Flowers

  8. 724. Find Pivot Index

  9. 448. Find All Numbers Disappeared in an Array

  10. 628. Maximum Product of Three Numbers

  11. 532. K-diff Pairs in an Array

  12. 897. Increasing Order Search Tree

  13. 872. Leaf-Similar Trees

  14. 876. Middle of the Linked List

  15. 203. Remove Linked List Elements

  16. 997. Find the Town Judge

  17. 270. Closest Binary Search Tree Value

  18. 687. Longest Univalue Path

  19. 783. Minimum Distance Between BST Nodes

  20. 235. Lowest Common Ancestor of a Binary Search Tree

Board Pagination Prev 1 2 3 4 Next
/ 4