Algorithm 2.

LAZYGREED for submodular maximization. [17]

1:	Input: f and m matroid constraints ${\mathcal{M}}_i=\left(E,{\mathcal{I}}_i\right)$.
2:	Output: An approximation solution $\widehat{A}$.
3:	$\widehat{A}\leftarrow \mathrm{Ø}$; Initialize priority queue Q.
4:	for $v\in E$ do
5:	INSERT $(Q,f(v))$
6:	end for
7:	while Q not empty do
8:	$(v,a)\leftarrow \text{POP}(Q)$
9:	if $(\{v\}\cup \widehat{A})\in {\cap }_i{\mathcal{I}}_i$ then
10:	isFresh ← $(\alpha =f(v\mid \widehat{A}))$
11:	if not isFresh then
12:	$\alpha \leftarrow f(v\mid \widehat{A})$
13:	end if
14:	if isFreash or α ≥ max(Q) then
15:	$\widehat{A}\leftarrow \widehat{A}\cup \left\{v\right\}$
16:	else
17:	INSERT(Q, (v, α))
18:	end if
19:	end if
20:	end while
21:	return $\widehat{A}$