From aef51cb613eacf30396bd2e545d9220386d22345 Mon Sep 17 00:00:00 2001
From: Gabriel Donnan <47415809+gabedonnan@users.noreply.github.com>
Date: Fri, 17 Feb 2023 14:31:03 +0000
Subject: [PATCH] Create min-bintree-diff.py

janky-ahh solution to find the minimum difference between nodes in a binary search tree, could be very easily optimised but im not gonna right now
---
 min-bintree-diff.py | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)
 create mode 100644 min-bintree-diff.py

diff --git a/min-bintree-diff.py b/min-bintree-diff.py
new file mode 100644
index 0000000..aa24684
--- /dev/null
+++ b/min-bintree-diff.py
@@ -0,0 +1,25 @@
+# Definition for a binary tree node.
+# class TreeNode:
+#     def __init__(self, val=0, left=None, right=None):
+#         self.val = val
+#         self.left = left
+#         self.right = right
+class Solution:
+    def minDiffInBST(self, root_node: Optional[TreeNode]) -> int:
+
+        def search(root: Optional[TreeNode], prevs: List[int]) -> int:
+            if len(prevs) > 0:
+                prevdiff = min([abs(root.val - prev) for prev in prevs])
+            else:
+                prevdiff = math.inf
+            #print(root.val, prevs, prevdiff)
+            if root.left == None and root.right == None:
+                return prevdiff
+            elif root.left == None and root.right != None:
+                return min([abs(root.val - root.right.val), search(root.right, prevs + [root.val]), prevdiff])
+            elif root.right == None and root.left != None:
+                return min([abs(root.val - root.left.val), search(root.left, prevs + [root.val]), prevdiff])
+            else:
+                return min([search(root.left, prevs + [root.val]), search(root.right, prevs + [root.val]), abs(root.val - root.left.val), abs(root.val - root.right.val), prevdiff])
+        return search(root_node, [])
+