Level order traversal

Author: ChSatyaSavith

102. Binary Tree Level Order Traversal.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<vector<int>> levelOrder(TreeNode* root)
+    {
+        queue<TreeNode*> q;
+        vector<vector<int>> toreturn;
+        if(root==NULL)
+        {
+            return toreturn;
+        }
+        q.push(root);
+
+        while(!q.empty())
+        {
+            int size = q.size();
+            vector<int> level;
+            for(int i = 0;i<size;i++)
+            {
+                level.push_back(q.front()->val);
+                if(q.front()->left)
+                {
+                    q.push(q.front()->left);
+                }
+                if(q.front()->right)
+                {
+                    q.push(q.front()->right);
+                }
+                q.pop();
+            }
+            toreturn.push_back(level);
+        }
+
+        return toreturn;
+    }
+};