We visit neighbours in the order in which they appear in this adjacency list
0: 1, 2
1: 0, 3
2: 1
3: 2, 4
4: 1, 2, 5
5: 3
Which of the following gives the postorder sequence from this traversal, i.e., is a list of the vertices in order of the time that the call to depth-first search on the vertices finishes.