Create 0530-minimum-absolute-difference-in-bst.kt

Author: a93a

Diff for: kotlin/0530-minimum-absolute-difference-in-bst.kt

@@ -0,0 +1,32 @@
+/**
+ * Example:
+ * var ti = TreeNode(5)
+ * var v = ti.`val`
+ * Definition for a binary tree node.
+ * class TreeNode(var `val`: Int) {
+ *     var left: TreeNode? = null
+ *     var right: TreeNode? = null
+ * }
+ */
+class Solution {
+
+    fun minDiffInBST(root: TreeNode?): Int {
+
+        var res = Integer.MAX_VALUE
+        var prev = -1 //Values in range (0 to 10^5)
+
+        fun dfs(root: TreeNode?) {
+            if(root == null) return  
+
+            dfs(root.left)
+            if(prev != -1) res = minOf(res, root.value - prev) 
+            prev = root.value
+            dfs(root.right)
+        }
+        
+        dfs(root)
+        return res
+    }
+
+    val TreeNode.value get() = this.`val`
+}