Given a binary tree, the task is to find the sum of the nodes which are visible in the left view. The left view of a binary tree is the set of nodes visible when the tree is viewed from the left.
Input: 1 / \ 2 3 / \ \ 4 5 6 Output: 7 1 + 2 + 4 = 7 Input: 1 / \ 2 3 \ 4 \ 5 \ 6 Output: 18
Approach: The problem can be solved using simple recursive traversal. We can keep track of the level of a node by passing a parameter to all the recursive calls. The idea is to keep track of the maximum level also and traverse the tree in a manner that the left subtree is visited before the right subtree. Whenever a node whose level is more than the maximum level so far is encountered, add the value of the node to the sum because it is the first node in its level (Note that the left subtree is traversed before the right subtree).
Below is the implementation of the above approach:
- Print Left View of a Binary Tree
- Iterative Method To Print Left View of a Binary Tree
- Sum of nodes in top view of binary tree
- Sum of nodes in the right view of the given binary tree
- Sum of nodes in bottom view of Binary Tree
- Print Nodes in Top View of Binary Tree
- Print nodes in the Top View of Binary Tree | Set 3
- Print nodes in top view of Binary Tree | Set 2
- Connect all nodes to their Left Neighbors in a Binary Tree
- Print all leaf nodes of a Binary Tree from left to right
- Print all leaf nodes of a binary tree from right to left
- Print leaf nodes in binary tree from left to right using one stack
- Print left and right leaf nodes separately in Binary Tree
- Change a Binary Tree so that every node stores sum of all nodes in left subtree
- Print All Leaf Nodes of a Binary Tree from left to right | Set-2 ( Iterative Approach )
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