Merge pull request neetcode-gh#1161 from t3chkid/main

Adds iterative solution to 104. Maximum Depth of Binary Tree in Kotlin
Jay-0331 · Sep 24, 2022 · 7186a2a · 7186a2a
2 parents 69f7d5d + 9fd6ddf
commit 7186a2a
Showing 1 changed file with 18 additions and 0 deletions.
diff --git a/kotlin/104-Maximum-Depth-Of-Binary-Tree.kt b/kotlin/104-Maximum-Depth-Of-Binary-Tree.kt
@@ -1,3 +1,5 @@
+import java.util.*
+
 /**
  * Example:
  * var ti = TreeNode(5)
@@ -18,4 +20,20 @@ class Solution {
 
  return 1 + Math.max(left, right)
  }
+
+ fun iterativeMaxDepth(root: TreeNode?): Int {
+ if (root == null) return 0
+ val callStack = Stack<Pair<TreeNode, Int>>().apply { add(Pair(root, 1)) }
+ var currentMaxDepth = 1
+ var temp: Pair<TreeNode, Int>
+ while (callStack.isNotEmpty()) {
+ temp = callStack.pop()
+ currentMaxDepth = maxOf(currentMaxDepth, temp.second)
+ with(temp.first) {
+ left?.let { callStack.add(Pair(it, currentMaxDepth + 1)) }
+ right?.let { callStack.add(Pair(it, currentMaxDepth + 1)) }
+ }
+ }
+ return currentMaxDepth
+ }
 }