Algorithm 2. Tour construction.
Input: Spanning tree $T$, traveling distance constraint $L$;
Output: A charging tour $P$ starts from and ends at $v_0$
1:	repeat
2:		compute shortest path in the $T$,$P:=\mathrm{LKH}(T)$
3:		If $C_{\mathrm{LKH}}(P)\le L$ then
4:			Declare $P$ is accepted
5:		else
6:			Delete the last added node from $T$
7:		end if
8:	until$P$ is accepted
9:	return$P$