Algorithm 4: MTCLM_COLOUR (G, $\mathcal{SU}$).

Input:graph G, $\mathcal{SU}$ Output: X,$\mathcal{CT}$. 1:$X=\{x_{ij}\leftarrow 0:\forall i\in \mathcal{S},j\in \mathcal{JU}\}$; 2:$\mathcal{CT}\leftarrow \varnothing$; 3:computer the optimal solution to the LP: $x^{*}$,$y^{*}$; 4:${\widehat{y}}_t\triangleq \lceil y_t^{*}H\rceil /H$; 5:${\widehat{x}}_{ij}\triangleq \lceil x_{ij}^{*}H\rceil /H$; 6:build auxiliary graph $\overline{G}$; 7:obtain a legal colouring of $\overline{G}$ greedily; 8: for $k\in [1,H]$ do 9:  calculate the number of targets covered by each colour k; 10: end for 11:obtain colour q with the maximum number of covered targets; 12:obtain the edges ${\mathcal{E}}_q$ coloured by q in graph $\overline{G}$; 13: for $(i,j^{\prime })\in {\mathcal{E}}_q$ do 14:  if$j^{\prime }$ is the duplication nodes of j in graph G then 15:   set $x_{ij}=1$; 16:   $\mathcal{CT}=\mathcal{CT}\bigcup {\mathcal{U}}_j$; 17:  end if 18: end for 19:return$X,\mathcal{CT}$;