1379 Find a Corresponding Node of a Binary Tree in a Clone of That Tree

1379 Find a Corresponding Node of a Binary Tree in a Clone of That Tree.java

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */

class Solution {
    public final TreeNode helper(final TreeNode n, final int v) {
        if (n == null) return null;
        if (n.val == v) return n;
        TreeNode l = helper(n.left, v);
        if (l != null) return l;
        TreeNode r = helper(n.right, v);
        if (r != null) return r;
        return null;
    }
    public final TreeNode getTargetCopy(final TreeNode original, final TreeNode cloned, final TreeNode target) {
        int v = target.val;
        return helper(cloned, v);
    }
}

/* Solution from leetcode
class Solution {
    public final TreeNode getTargetCopy(final TreeNode original, final TreeNode cloned, final TreeNode target) {
        if( original == null ) return cloned;
        return dfs( original, cloned, target );
    }
    
    public TreeNode dfs( final TreeNode original, final TreeNode cloned, final TreeNode target ) {
        if( original == target ) return cloned;
        if( original.left != null ) {
            TreeNode tmp = dfs( original.left, cloned.left, target );
            if( tmp != null ) return tmp;
        }
        if( original.right != null ) {
           TreeNode tmp = dfs( original.right, cloned.right, target );
            if( tmp != null ) return tmp;
        }
        return null;
    }
}
*/