Adjacency List Build

Problem

Build an undirected adjacency list for n nodes labeled 0 to n-1 from a list of edges.

edges is a list of [u, v] pairs. Return a list of n lists, where the i-th list holds the neighbors of node i in ascending order.

Hint

Append each endpoint to the other node's list, then sort every list.

case 1

in: [4,[[0,1],[1,2],[2,3]]]

expected: [[1],[0,2],[1,3],[2]]

case 2

in: [3,[[0,1],[0,2],[1,2]]]

expected: [[1,2],[0,2],[0,1]]

case 3

in: [2,[]]

expected: [[],[]]

case 4

in: [1,[]]

expected: [[]]

Starter codePython

def build_adjacency_list(n, edges):
    # Your code here
    pass

4 test cases · run your code against them in the editor