. Author manuscript; available in PMC: 2024 Jun 4.

Published in final edited form as: Res Comput Mol Biol. 2020 Apr 21;12074:37–53. doi: 10.1007/978-3-030-45257-5_3

Algorithm 1.

Improved hitting number calculation. Input: $G = (V, E)$

1:	$D \leftarrow [\| V \|] [𝓁 + 1]$ , with $[\| V \|] [0]$ initialized to 1
2:	$F_{c u r r} \leftarrow [\| V \|]$
3:	$F_{p r e v} \leftarrow [\| V \|]$ initialized to 1
4:	$T \leftarrow [\| V \|]$ initialized to 0
5:	for $1 \leq i \leq 𝓁$ do:
6:	for $v \in V$ do:
7:	for $(v, u) \in E$ do:
8:	$D [v] [i] + = D [u] [i - 1]$
9:	for $1 \leq i \leq 𝓁 + 1$ do:
10:	for $v \in V$ do:
11:	$F_{c u r r} [v] = 0$
12:	for $(u, v) \in E$ do:
13:	$F_{c u r r} [v] + = F_{p r e v} [u]$
14:	$T [v] + = F_{p r e v} [v] \cdot D [v] [𝓁 - i + 1]$
15:	$F_{p r e v} = F_{c u r r}$
16:	return $T$