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Leetcode : 235. Lowest Common Ancestor of a Binary Search Tree

Leetcode : 236. Lowest Common Ancestor of a Binary Tree

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//leetcode 235
class Solution {
public:
    TreeNode* lowestCommonAncestor(TreeNode* root, TreeNode* p, TreeNode* q) {
        if(root == nullptr)
            return root;
        if(root->val > p->val && root->val > q->val)
            return lowestCommonAncestor(root->left, p, q);
        else if(root->val<p->val && root->val<q->val)
            return lowestCommonAncestor(root->right, p, q);
        else
             return root;
    }
};

//leetcode 236
class Solution {
public:
    TreeNode* lowestCommonAncestor(TreeNode* root, TreeNode* p, TreeNode* q) {
        if(root==nullptr)
            return root;
        if(root->val == p->val || root->val == q->val)
            return root;
        TreeNode* leftNode = lowestCommonAncestor(root->left, p, q);
        TreeNode* rightNode = lowestCommonAncestor(root->right, p, q);
        if(leftNode && rightNode)
            return root;
        return leftNode?leftNode:rightNode?rightNode:nullptr;
    }
};