Count Complete Tree Nodes

/**
 * 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:
    int countNodes(TreeNode* root) {
        
        int height=1;
        if(root==NULL)
            return 0;
        TreeNode * temp=root;
        stack<TreeNode *> s1;
        while(temp!=NULL)
        {
            height++;
            s1.push(temp);
            temp=temp->right;
        }
        int count=(int)(pow(2,height)-1);
        bool flag=0;
        int len=1;
        int leftVal=0;
        int rightVal=0;
        while(!s1.empty())
        {
            len++;
            TreeNode * temp=s1.top();
            s1.pop();
            if(right==0)
                rightVal=getCount(temp->right);
            else
                rightVal=leftVal+right+1;
            leftVal=getCount(temp->left);
            if(leftVal!=rightVal)
                break;
        }
        int lack=(int)(pow(2,len)-1-(leftVal+rightVal+1));
        int res=count-lack;
        return res;
        
    }
    int getCount(TreeNode * node)
    {
        if(node==NULL)
            return 0;
        int res=0;
        queue<TreeNode *> q;
        q.push(node);
        while(!q.empty())
        {
            res++;
            TreeNode * temp=q.front();
            q.pop();
            if(temp->left!=NULL)
                q.push(temp->left);
            if(temp->right!=NULL)
                q.push(temp->right);
        }
        return res;
    }
};