A Hybrid Bat Algorithm with Path Relinking for Capacitated Vehicle Routing Problem

Algorithm 2

Local_Search_Phase (𝑆).

𝑆^′←𝑆;

{𝑠𝑟}←𝐶𝑜𝑛𝑠𝑡𝑟𝑢𝑐𝑡_Sub-route(𝑆^′);

for each sub-route 𝑠𝑟 do

  𝑠𝑟^′←2-opt (𝑠𝑟); // carry out the 2-opt operation

end

𝑆^′←𝐶𝑜𝑛𝑠𝑡𝑟𝑢𝑐𝑡_Indiviaual 𝑠𝑟^′;

if 𝑓(𝑆^′)<𝑓(𝑆)   then

  𝑆←𝑆^′

end

return    𝑆