fork download
copy 
  1. #include <bits/stdc++.h>
  2. using namespace std;
  3. struct TreeNode{
  4. 	int val;
  5. 	TreeNode* right;
  6. 	TreeNode* left;
  7. 	TreeNode(int val):left(nullptr),right(nullptr),val(val){};
  8. };
  9. bool sym(TreeNode* left,TreeNode* right){
  10. 	if(left == nullptr && right == nullptr)return true;
  11. 	if(left == nullptr || right == nullptr)return false;
  12.  
  13. 	if(left->val!=right->val)return false;
  14.  
  15. 	return sym(left->left,right->right)&&sym(left->right,right->left);
  16. }
  17. bool isSymm(TreeNode* root){
  18.  
  19.   if(root == nullptr)return true;
  20.   return sym(root->left,root->right);
  21.  
  22. }
  23. TreeNode* buildTree(){
  24. 	int x;cin>>x;
  25. 	if(x==-1)return nullptr;
  26. 	TreeNode* root = new TreeNode(x);
  27.  
  28. 	queue<TreeNode*>q;
  29. 	q.push(root);
  30.  
  31. 	while(!q.empty()){
  32. 		auto u = q.front();
  33. 		q.pop();
  34.  
  35. 		if(cin>>x && x!=-1){
  36. 			u->left = new TreeNode(x);
  37. 			q.push(u->left);
  38. 		}
  39.  
  40. 		if(cin>>x && x!=-1){
  41. 			u->right = new TreeNode(x);
  42. 			q.push(u->right);
  43. 		}
  44. 	}
  45. 	return root;
  46. }
  47. int main() {
  48.     TreeNode* root = buildTree();
  49.  
  50.      bool ans = isSymm(root);
  51.      cout<<ans;
  52.  
  53. 	return 0;
  54. }
Success #stdin #stdout 0.01s 5288KB
comments (?)
stdin
copy 
1 2 2 -1 3 -1 3
stdout
copy 
Standard output is empty
https://ideone.com/X0wGYn
language:
C++14 (gcc 8.3)
created:
2 days ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!