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authorMarcin Chrzanowski <mc370754@students.mimuw.edu.pl>2021-12-07 13:32:21 +0100
committerMarcin Chrzanowski <mc370754@students.mimuw.edu.pl>2021-12-07 13:32:21 +0100
commitcb614b7456dade96de346a53f4873c7db23b92ba (patch)
treee90531611acc512442dcc95dfd09692385b8750b
parent81fdd3f346ed286cbf413515e66f21fcd3c28d27 (diff)
Finalize subtree with hole explanation
-rw-r--r--mgr.tex14
1 files changed, 8 insertions, 6 deletions
diff --git a/mgr.tex b/mgr.tex
index 1c1644b..015e0ef 100644
--- a/mgr.tex
+++ b/mgr.tex
@@ -1041,14 +1041,16 @@ Our algorithm for branch infix regular queries dealt with top-down queries, but
regular languages are reversible. So we preprocess $T$ for branch infix regular
queries for each language $L_{q, q'}^R$. Now a query about whether the word on
the path from $x$ down to $y$ belongs to $L_{q, q'}^R$ is the same as asking if
-the word from $y$ up to $x$ belongs to $L{q,q'}$.
+the word from $y$ up to $x$ belongs to $L{q,q'}$. Note that the number of
+languages we need to preprocess for is constant in the size of the tree -- it
+only depends on the size of the automaton.
-Now to compute $v$'s state after the relabeling of $T$, given we've already
-computed $w$'s new state $q$, take $v'$ -- $v$'s child in the direction of $w$,
-find $q' \in Q$ such that the path from $v'$ to $w$ belongs to $L_{q, q'}^R$
+Given the subtree of $x$ with hole $y$, once we've computed $y$'s new state $q$,
+to compute $x$'s new state, take $x'$ -- $x$'s child in the direction of $y$,
+find $q' \in Q$ such that the path from $x'$ to $y$ belongs to $L_{q, q'}^R$
(using branch infix regular queries; since $A$ is deterministic, there will be
-exactly one such $q'$), then from $q'$, the state of $v$'s other child, and
-$v$'s new label, use $A$'s transition function to compute $v$'s new state.
+exactly one such $q'$). Now from $q'$, the state of $x$'s other child, and
+$x$'s new label, use $A$'s transition function to compute $x$'s new state.
Since $T$'s root is the root of one of the parts of our LCA partition, in the
end we will know whether or not $A$ accepts $T$ after relabeling. Handling each