How to Solve Binary Tree Right Side View Using BFS in Java

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The right side view of a binary tree returns the last visible node at each level when the tree is viewed from the right. A level-order traversal (BFS) is the optimal approach, processing nodes level by level from left to right. At each level, the last node encountered is recorded as part of the right-side view. The algorithm uses a queue, tracks level size, and captures the node at index size-1 for each level. Both time and space complexity are O(N), where N is the total number of nodes in the tree.

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