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/**
* 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 xdepth=-1;
int ydepth=-1;
TreeNode* xparent;
TreeNode* yparent;
void dfs(TreeNode* root,int x,int y, int depth)
{
if(xdepth!=-1&&ydepth!=-1) return;
if(root->right!=nullptr)
{
if(root->right->val==x)
{
xdepth=depth;
xparent=root;
}
if(root->right->val==y)
{
ydepth=depth;
yparent=root;
}
dfs(root->right,x,y,depth+1);
}
if(root->left!=nullptr)
{
if(root->left->val==x)
{
xdepth=depth;
xparent=root;
}
if(root->left->val==y)
{
ydepth=depth;
yparent=root;
}
dfs(root->left,x,y,depth+1);
}
return;
}
bool isCousins(TreeNode* root, int x, int y) {
if(root==nullptr) return false;
dfs(root,x,y,0);
if((xparent!=yparent)&&(xdepth==ydepth))
return true;
else return false;
}
};