LeetCode 236. Lowest Common Ancestor of a Binary Tree

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */
class Solution {
public:
    TreeNode* lowestCommonAncestor(TreeNode* root, TreeNode* p, TreeNode* q) {
        
        if(p->val==root->val||q->val==root->val)
            return root;
    
        TreeNode* term=NULL;
        TreeNode* term2=NULL;
        if(root->left!=NULL)
            term = lowestCommonAncestor(root->left,p,q);
       
        if(root->right!=NULL)
            term2 = lowestCommonAncestor(root->right,p,q);
      
        if(term!=NULL&&term2!=NULL)
            return root;

        if(term==NULL)
            return term2;
        if(term2==NULL)
            return term;
        
        return root;
        
    }
};