Start from the root and traverse the tree using a recursive or iterative method.
Check at each step whether the current node matches the target node.
Keep track of the depth as you traverse down the tree.
If the node is found, return the depth; otherwise, continue searching through left and right subtrees.
If the entire tree is traversed and the node is not found, return -1.

Approach

Use recursion to explore the left and right subtrees.
Pass the current depth as an argument to keep track of how far we have traversed from the root.
If the target node is found, return the current depth.
If traversal completes and the target node is not found, return -1.

Code

[{"language":"Java","code":"class Solution {\n    public static int findDepth(TreeNode root, int target) {\n        return dfsHelper(root, target, 0);\n    }\n\n    private static int dfsHelper(TreeNode node, int target, int currentDepth) {\n        if (node == null) return -1; // Base case: Node is not found\n\n        if (node.val == target) return currentDepth; // Target node found\n\n        // Check left and right subtrees\n        int left = dfsHelper(node.left, target, currentDepth + 1);\n        if (left != -1) return left; // Found in left subtree\n\n        int right = dfsHelper(node.right, target, currentDepth + 1);\n        return right; // Found in right subtree or not found (-1)\n    }\n}","lang":"java","html":"<pre class=\"shiki shiki-themes github-light github-dark\" style=\"background-color:#fff;--shiki-dark-bg:#24292e;color:#24292e;--shiki-dark:#e1e4e8\" tabindex=\"0\"><code><span class=\"line\"><span style=\"color:#D73A49;--shiki-dark:#F97583\">class</span><span style=\"color:#6F42C1;--shiki-dark:#B392F0\"> Solution</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\"> {</span></span>\n<span class=\"line\"><span style=\"color:#D73A49;--shiki-dark:#F97583\">    public</span><span style=\"color:#D73A49;--shiki-dark:#F97583\"> static</span><span style=\"color:#D73A49;--shiki-dark:#F97583\"> int</span><span style=\"color:#6F42C1;--shiki-dark:#B392F0\"> findDepth</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">(TreeNode </span><span style=\"color:#E36209;--shiki-dark:#FFAB70\">root</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">, </span><span style=\"color:#D73A49;--shiki-dark:#F97583\">int</span><span style=\"color:#E36209;--shiki-dark:#FFAB70\"> target</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">) {</span></span>\n<span class=\"line\"><span style=\"color:#D73A49;--shiki-dark:#F97583\">        return</span><span style=\"color:#6F42C1;--shiki-dark:#B392F0\"> dfsHelper</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">(root, target, </span><span style=\"color:#005CC5;--shiki-dark:#79B8FF\">0</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">);</span></span>\n<span class=\"line\"><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">    }</span></span>\n<span class=\"line\"></span>\n<span class=\"line\"><span style=\"color:#D73A49;--shiki-dark:#F97583\">    private</span><span style=\"color:#D73A49;--shiki-dark:#F97583\"> static</span><span style=\"color:#D73A49;--shiki-dark:#F97583\"> int</span><span style=\"color:#6F42C1;--shiki-dark:#B392F0\"> dfsHelper</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">(TreeNode </span><span style=\"color:#E36209;--shiki-dark:#FFAB70\">node</span><

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