题解 | #判断一棵二叉树是否为搜索二叉树和完全二叉树#

class Solution {
public:
    /**
     * 
     * @param root TreeNode类 the root
     * @return bool布尔型vector
     */
    vector<bool> judgeIt(TreeNode* root) {
        return {issearch(root),iswhole(root)};
    }
    bool iswhole(TreeNode *root)
    {
        if(!root)
            return true;
        queue<TreeNode* > q;
        q.push(root);
        bool flag=false;
        while(!q.empty())
        {
            int n=q.size();
            while(n--)
            {
                TreeNode* p=q.front();
                q.pop();
                if(p->left)
                    q.push(p->left);
                if(p->left&&p->right)
                    q.push(p->right);
                else if(!p->left&&p->right)
                    return false;
                else if(!p->right)
                {
                    flag=true;
                    break;
                }
            }
            while(flag&&!q.empty())
            {
                TreeNode* p=q.front();
                q.pop();
                if(p->left||p->right)
                    return false;
            }
        }
        return true;
    }
    bool issearch(TreeNode *root)
    {
        if(!root)
            return true;
        TreeNode *l,*r;
        if(root->left)
        {
            if(root->val<root->left->val||!issearch(root->left))
                return false;
            l=root->left;
            while(l->right)
                l=l->right;
            if(l->val>root->val)
                return false;
        }
        if(root->right)
        {
            if(root->val>root->right->val||!issearch(root->right))
                return false;
            r=root->right;
            while(r->left)
                r=r->left;
            if(r->val<root->val)
                return false;
        }
        return true;
    }
};