Top View of Binary Tree | Level Order Traversal

Short summary

Binary tree top view uses BFS with horizontal distance tracking: assign each node an HD (root=0, left child=HD-1, right child=HD+1), store only the first node at each unique distance in a TreeMap, and traverse left-to-right. Time O(N log N), space O(N).

• •Apply BFS level-order traversal combined with horizontal distance assignment
• •Store only the first (topmost) node encountered at each horizontal distance
• •Use TreeMap to track and retrieve nodes in sorted order by distance

Generated with AI, which can make mistakes.