Algorithm 2 Exception handling algorithm
Input: all nodes' neighborhood N; error location permutation S'.
Output: node location permutation S.
1.	Find the missing node M;
2.	If the first two elements in NM are neighborhood in the error ordering S' then
3.	put the missing node M in the S' between the two elements in NM;
4.	else
5.	break;
6.	S (1) = S' (n), use Alogorithm1 to derive ordering S
7.	If S is the reversion of S' then
8.	S = S';
9.	else
10.	S = null;
11.	end if 7. output the location permutation S