Given a Binary Tree, the task is to flatten it in order of Level order traversal of the tree. In the flattened binary tree, the left node of all the nodes must be NULL.
Input: 1 / \ 5 2 / \ / \ 6 4 9 3 Output: 1 5 2 6 4 9 3 Input: 1 \ 2 \ 3 \ 4 \ 5 Output: 1 2 3 4 5
Approach: We will solve this problem by simulating the Level order traversal of Binary Tree as follows:
- Create a queue to store the nodes of Binary tree.
- Create a variable “prev” and initialise it by parent node.
- Push left and right children of parent in the queue.
- Apply level order traversal. Lets say “curr” is front most element in queue. Then,
- If ‘curr’ is NULL, continue.
- Else push curr->left and curr->right in the queue
- Set prev = curr
Below is the implementation of the above approach:
Time Complexity: O(N)
Space Complexity: O(N) where N is the size of Binary Tree.
- Flatten binary tree in order of post-order traversal
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- Flatten Binary Tree in order of Zig Zag traversal
- Density of Binary Tree using Level Order Traversal
- Perfect Binary Tree Specific Level Order Traversal
- Perfect Binary Tree Specific Level Order Traversal | Set 2
- Given level order traversal of a Binary Tree, check if the Tree is a Min-Heap
- Insertion in n-ary tree in given order and Level order traversal
- Check if the level order traversal of a Binary Tree results in a palindrome
- Calculate height of Binary Tree using Inorder and Level Order Traversal
- Check if the given array can represent Level Order Traversal of Binary Search Tree
- Level Order Tree Traversal
- Zig Zag Level order traversal of a tree using single queue
- General Tree (Each node can have arbitrary number of children) Level Order Traversal
- Level Order Successor of a node in Binary Tree
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Improved By : Rajput-Ji