Merge pull request #85 from InflixOP/patch1

Create #199. Binary Tree Right Side View.cpp

Author: InflixOP

#199. Binary Tree Right Side View.cpp

@@ -0,0 +1,46 @@
+/**
+ * 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:
+        vector<int> ans;
+        vector<int> levelOrder(TreeNode* root,vector<int> &ans) {
+            queue<TreeNode*> q;
+            vector<int> a;
+            q.push(root);
+            q.push(NULL);
+            while(!q.empty()){
+                TreeNode* temp=q.front();
+                q.pop();
+                if(temp==NULL){
+                    reverse(a.begin(),a.end());
+                    ans.push_back(a[0]);
+                    a.clear();
+                    if(!q.empty()){
+                        q.push(NULL);
+                    }
+                }
+                else{
+                    a.push_back(temp->val);
+                    if(temp->left) q.push(temp->left);
+                    if(temp->right) q.push(temp->right);
+                }
+            }
+          return ans;
+        }
+        vector<int> rightSideView(TreeNode* root) {
+            if(root==NULL){
+                return ans;
+            }
+            levelOrder(root,ans);
+            return ans;
+        }
+    };