力扣刷题记录41.1-----101. 对称二叉树

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一、题目

二、代码

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
 *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
 * };
 */
class Solution {
public:
    bool isSymmetric(TreeNode* root)
    {  

       int i,j;
       queue<TreeNode*> range_first_tree;
       int queue_size; 
       TreeNode* process_node;
       vector<int> each_layer;
       vector<int> each_layer_reverse;      

       bool return_bool=1;
       
       
       range_first_tree.push(root);
       //核心:每层一次性做完    每一层的nulptr也应该入栈
       while(!range_first_tree.empty())
       {
         queue_size=range_first_tree.size();
         for(i=0;i<queue_size;i++)
         {
            process_node=range_first_tree.front();
            range_first_tree.pop();

            if(process_node!=nullptr)    each_layer.push_back(process_node->val);
            else   each_layer.push_back(-200);
          
            if(process_node!=nullptr)
            {
             range_first_tree.push(process_node->left);
             range_first_tree.push(process_node->right);
            }

         }
         each_layer_reverse=each_layer;
         reverse(each_layer_reverse.begin(),each_layer_reverse.end());

         std::cout<<"each layer"<<std::endl;
         for(i=0;i<each_layer.size();i++)
         {
              std::cout<<"   "<<each_layer[i];

         }
         std::cout<<std::endl;

         std::cout<<"each_layer_reverse "<<std::endl;
         for(i=0;i<each_layer_reverse.size();i++)
         {
              std::cout<<"   "<<each_layer_reverse[i];

         }
         std::cout<<std::endl;


         for(i=0;i<each_layer.size();i++)
         {
             if(each_layer[i]!=each_layer_reverse[i]) 
             {
                 return_bool=0;
                 break;
             }
         }
         each_layer.clear();
         each_layer_reverse.clear();
         if(return_bool==0) break;

       }        


       return return_bool;
    }
};
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三、运行结果