Directed Adjacency List

Problem

Build an adjacency list for a directed graph from an edge list.

edges is a list of directed [u, v] pairs. Return a list of n lists where entry u holds the sorted out-neighbors of node u. Nodes with no outgoing edges get an empty list.

Hint

Only record u to v for each directed edge, then sort every neighbor list.

Test cases

case 1

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

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

case 2

in: [4,[]]

expected: [[],[],[],[]]

case 3

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

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

case 4

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

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

Starter codePython

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

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