“…Cooperative methods [6,13,43,15,31,46] iteratively alternate between a search for a cyclic tour and another search of a collection plan, keeping one of the two unchanged while searching for the other until no further improvement. Full-encoding methods [26,42,13,14,45] deals with the entire TTP problem at a time using cyclic tour and collection plan changing operators within the same search framework. Hyper-heuristic methods [1,25,24,16] generate or select low level heuristics as neighbourhood operators for cyclic tours or collection plans and use them in search.…”