Dsa
Trees
Easy
Sum of Left Leaves
Calculate the sum of all left leaves in a binary tree. A left leaf is a leaf node that is the left child of its parent.
Input format:
- The first line contains an integer N, the number of nodes in the tree.
- The following N lines contain integers representing each node's value in level-order traversal. Use -1 to indicate 'null' nodes.
Output format:
- Print a single integer representing the sum of all left leaves.
Example:
Input:
5
1
2
3
-1
-1
4
-1
-1
Output:
2
Key concepts
treesleavessum
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