Algorithm 2: ND-C_sort function

$$\mathrm{Function}: (\mathrm{Hpopulation}, \overrightarrow{P_{\ast }^t}) = \mathrm{ND}-\mathrm{C}\_\mathrm{sort} (\mathrm{Hpopulation}, \mathrm{Ppopulation}, \mathrm{capacity})$$

Input: Hpopulation, Ppopulation, capacity

$$\mathrm{Output}: \mathrm{Hpopulation}, \overrightarrow{P_{\ast }^t}$$

1: Add Ppopulation into Hpopulation

2: Update Hpopulation with the non-dominated solution of Hpopulation based on formula (6)

3: The solutions in Hpopulation are sorted by crowding degree by formula (14)

4: If size (Hpopulation) > capacity then

5:  Solutions that have poor crowding degrees are eliminated

6: End if

7: The optimal solution $\overrightarrow{P_{\ast }^t}$ is selected from Hpopulation by the roulette selection method by using (15)