My code failed at test case: {0,1,5#1,2,5#2,3#3,4,4#4,5,5#5}

If I understand correctly:

- node 0 has 1 and 5 as its neighbors
- node 1 has 2 and 5 as its neighbors
- node 2 has 3 as its neighbors
**node 3 has 4 as its neighbors****node 4 has 5 as its neighbors**

I don't understand #4 and #5, why is it described as *3,4,4* and *4,5,5* rather than *3,4* and *4,5* ?