270. Closest Binary Search Tree Value
Problem:
Given a non-empty binary search tree and a target value, find the value in the BST that is closest to the target.
Note: Given target value is a floating point. You are guaranteed to have only one unique value in the BST that is closest to the target.
Solutions:
/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode(int x) { val = x; }
* }
*/
public class Solution {
private double min = 0;
private int cand = 0;
public int closestValue(TreeNode root, double target) {
min = Double.MAX_VALUE;
cand = 0;
cv(root, target);
return cand;
}
private void cv(TreeNode node, double target) {
if (node == null) {
return;
}
double diff = Math.abs(node.val - target);
if (diff < min) {
min = diff;
cand = node.val;
}
if (target > node.val) {
cv(node.right, target);
}
else {
cv(node.left, target);
}
}
}