给你一棵所有节点为非负值的二叉搜索树,请你计算树中任意两节点的差的绝对值的最小值
/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode(int x) { val = x; }
* }
*/
class Solution {
int pre=-1;
int min=10000;
public int getMinimumDifference(TreeNode root) {
f(root);
return min;
}
public void f(TreeNode root){
if(root!=null){
f(root.left);
if(pre==-1){
pre=root.val;
}else{
min=Math.min(min,root.val-pre);
pre=root.val;
}
f(root.right);
}
}
}