Merge pull request #161 from FazeelUsmani/cousins-in-BT

abdulbasith007 · web-flow · commit 8b4d924905c5 · 2021-10-23T20:29:01.000+05:30
Create 18_cousinsInBT.cpp
diff --git a/10 October LeetCode Challenge 2021/18_cousinsInBT.cpp b/10 October LeetCode Challenge 2021/18_cousinsInBT.cpp
@@ -0,0 +1,21 @@
+class Solution {
+public:
+    void rec(TreeNode* root, int x, int y, int d, int parent) {
+        if (!root) return;
+        
+        if (root->val == x) dx = d, x_par = parent;
+        if (root->val == y) dy = d, y_par = parent;
+        
+        if (dx != -1 && dy != -1) return;
+        
+        rec(root->left, x, y, d+1, root->val);
+        rec(root->right, x, y, d+1, root->val);
+    }
+    bool isCousins(TreeNode* root, int x, int y) {
+        rec(root, x, y, 0, -1);
+        return dx == dy && x_par != y_par;
+    }
+    
+private:
+    int dx = -1, dy = -1, x_par = -1, y_par = -1;
+};
