Hu Chunming / sip_server

0 --> 2
1 --> 1 3 4
2 --> 1 3 4
3 --> 1 4
4 --> 0 1
0 --> 2
1 --> 1 3 4
2 --> 1 3 4
3 --> 1 4
4 --> 0 1
distances: 0 2 1 2 2
parent[0] = 0
parent[1] = 2
parent[2] = 0
parent[3] = 2
parent[4] = 2