199. Binary Tree Right Side View

Author: amitbansal7

binary-tree-right-side-view.cpp

@@ -0,0 +1,35 @@
+//Runtime: 3 ms
+class Solution {
+public:
+    vector<int> rightSideView(TreeNode* root) {
+        queue<pair<int, TreeNode* > >Q;
+        Q.push(make_pair(1, root));
+        vector<int>res;
+        if(!root)
+            return res;
+        int maxlvl = 1;
+        int prev = root->val;
+        while(!Q.empty())
+        {
+            pair<int,TreeNode*> t = Q.front();
+            Q.pop();
+
+            if(t.first > maxlvl)
+            {
+                res.push_back(prev);
+                maxlvl++;
+            }
+            prev = t.second->val;
+            if(t.second->left)
+                Q.push(make_pair(t.first+1, t.second->left));
+
+            if(t.second->right)
+                Q.push(make_pair(t.first+1, t.second->right));
+        }
+
+        res.push_back(prev);
+
+        return res;
+    }
+
+};