Problem Brief

Tree Node Relationship

FULLTIMENEW GRADPHONE SCREEN

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You are given an undirected tree with nodes numbered from 0 to n - 1, rooted at node 0. For two queried nodes, classify their relationship.

Return "siblings" if the two nodes have the same parent. Return "cousins" if they are at the same depth but have different parents. Otherwise, return "others".

1Example 1

Input

n = 7, edges = [[0,1],[0,2],[1,3],[1,4],[2,5],[2,6]], nodeA = 3, nodeB = 4

Output

"siblings"

Explanation

Nodes 3 and 4 share parent 1.

2Example 2

Input

n = 7, edges = [[0,1],[0,2],[1,3],[1,4],[2,5],[2,6]], nodeA = 3, nodeB = 5

Output

"cousins"

Explanation

Nodes 3 and 5 are both depth 2, but their parents are different.

3Example 3

Input

n = 7, edges = [[0,1],[0,2],[1,3],[1,4],[2,5],[2,6]], nodeA = 1, nodeB = 6

Output

"others"

Explanation

The two nodes are at different depths.

Constraints

Limits and guarantees your solution can rely on.

The input graph is a valid tree rooted at node 0. Both queried nodes are valid node ids.