Algorithm 1 task level division

Require:   the task set $\mathcal{T}$ Ensure:   $\mathcal{L}={\left\{L_j\right\}}_{t_j\in \mathcal{T}}$ 1:Set ${\mathcal{T}}^{\prime }=\mathcal{T}$; 2:for each $t_j$ in $\mathcal{T}$ do 3: Set $C_j^{\prime }=C_j$; 4:Set $k=1$; 5:while${\mathcal{T}}^{\prime }\ne \varphi$do 6: for each task $t_j\in {\mathcal{T}}^{\prime }$ do 7:  if $C_j^{\prime }=\varphi$ then 8:   Set $L_j=k$; 9: for each task $t_j\in {\mathcal{T}}^{\prime }$ do 10:  for each task $t_q\in C_j^{\prime }$ do 11:   if $L_q=k$ then 12:    Delete $t_q$ from set $C_j^{\prime }$; 13:  if $L_j=k$ then 14:   Delete $t_j$ from set ${\mathcal{T}}^{\prime }$; 15: $k++$; 16:return$\mathcal{L}={\left\{L_j\right\}}_{t_j\in \mathcal{T}}$;