Recursive Simple Java Solution.

  • 0

    class Solution {
    public TreeNode lowestCommonAncestor(TreeNode root, TreeNode p, TreeNode q) {
    if(root == p || root == q || root == null) return root;

        boolean is_p_on_left = includes(root.left, p);
        boolean is_q_on_left = includes(root.left, q);
        if(is_p_on_left != is_q_on_left) return root;
        return is_p_on_left ? lowestCommonAncestor(root.left, p, q):lowestCommonAncestor(root.right, p, q);
    public boolean includes(TreeNode root, TreeNode node) {
        if(root == null) return false;
        if(root == node) return true;
        return includes(root.left, node) || includes(root.right, node);


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