855. Bottom View of Binary Tree

Given the root of a binary tree, return its bottom view — the nodes visible when viewed from directly below, ordered left to right by horizontal distance. The root has horizontal distance 0; a left child is one less, a right child one more. For each horizontal distance the bottommost node (last reached in level order) is visible. The tree is given as a level-order array.

Input: A level-order array of the tree.

Output: Array — bottom-view node values, left to right.

Examples

Input: [1,2,3,4,5,6,7]
Output: [4,2,6,3,7]
Explanation: The lowest node per horizontal distance.

Input: [1]
Output: [1]
Explanation: Single node.

Input: []
Output: []
Explanation: Empty tree.

Constraints

• 0<=nodes<=10^4
• -1000<=value<=1000

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