sadie100: maximum depth of binary tree solution

Author: sadie100

maximum-depth-of-binary-tree/sadie100.ts

@@ -0,0 +1,34 @@
+/**
+ * Definition for a binary tree node.
+ * class TreeNode {
+ *     val: number
+ *     left: TreeNode | null
+ *     right: TreeNode | null
+ *     constructor(val?: number, left?: TreeNode | null, right?: TreeNode | null) {
+ *         this.val = (val===undefined ? 0 : val)
+ *         this.left = (left===undefined ? null : left)
+ *         this.right = (right===undefined ? null : right)
+ *     }
+ * }
+ */
+
+/*
+ DFS로 노드를 탐색해가며 최대깊이를 찾는다
+ 
+ 시간 복잡도 : O(N - binary tree의 깊이)
+
+ */
+
+function maxDepth(root: TreeNode | null): number {
+  let result = 0
+  const search = (node, floor) => {
+    if (!node) return
+    result = Math.max(floor, result)
+
+    search(node.left, floor + 1)
+    search(node.right, floor + 1)
+  }
+
+  search(root, 1)
+  return result
+}