# Blogs Hub

### by Sumit Chourasia | Oct 07, 2020 | Category :coding | Tags : algorithmbinary-treedata-structureeasyleetcodetree #### Minimum Absolute Difference in BST - Tree - Easy - LeetCode

Given a binary search tree with non-negative values, find the minimum absolute difference between values of any two nodes.

Example:

Input:

1
\
3
/
2

Output:
1

Explanation:
The minimum absolute difference is 1, which is the difference between 2 and 1 (or between 2 and 3).

Note:

There are at least two nodes in this BST.

``````/**
* Definition for a binary tree node.
* public class TreeNode {
*     public int val;
*     public TreeNode left;
*     public TreeNode right;
*     public TreeNode(int val=0, TreeNode left=null, TreeNode right=null) {
*         this.val = val;
*         this.left = left;
*         this.right = right;
*     }
* }
*/
public class Solution {
int min = int.MaxValue;
int? prev = null;
public int GetMinimumDifference(TreeNode root) {
InOrder(root);
return min;
}

private void InOrder(TreeNode root){
if(root == null){
return;
}

InOrder(root.left);
if(prev!=null){
min = Math.Min(Math.Abs(root.val-(int)prev),min);
}
prev = root.val;
InOrder(root.right);
}
}``````

Time Complexity: O(n)

Space Complexity: O(1)