K Distance Nodes in Tree | Dataford Interview Questions

Find the k distance nodes in a binary tree.

Implement distance_k_nodes(root, target, k), where root is a nested binary tree dictionary, target is a unique node value, and k is a nonnegative distance. Return node values exactly k edges from the target, ordered by BFS discovery using left child, right child, then parent links. Return [] if the tree is empty, the target is absent, or no nodes are at that distance.

Each node has the form {"val": value, "left": node_or_null, "right": node_or_null}.

Constraints

0 <= number of nodes <= 1000
Node values are integers
Node values are unique
0 <= k <= 1000
Each node has keys val, left, and right
The tree contains no cycles

Function Signature

def distance_k_nodes(root, target, k):

Your question is K Distance Nodes in Tree. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem

Find the k distance nodes in a binary tree.

Each node has the form {"val": value, "left": node_or_null, "right": node_or_null}.

Constraints

0 <= number of nodes <= 1000
Node values are integers
Node values are unique
0 <= k <= 1000
Each node has keys val, left, and right
The tree contains no cycles

Function Signature

def distance_k_nodes(root, target, k):

Your question is K Distance Nodes in Tree. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.