Detecting Useless Transitions in Pushdown Automata

TL;DR

This paper introduces an algorithm to identify and eliminate useless transitions in pushdown automata by analyzing reachable stack contents and their potential to lead to accepting states, improving automaton efficiency.

Contribution

The paper presents a novel algorithm combining forward and backward procedures to detect transitions that are never used in any accepting run of a pushdown automaton.

Findings

The algorithm effectively identifies useless transitions.

It improves automaton analysis by reducing unnecessary transitions.

The method enhances understanding of pushdown automaton behavior.

Abstract

Pushdown automata may contain transitions that are never used in any accepting run of the automaton. We present an algorithm for detecting such useless transitions. A finite automaton that captures the possible stack content during runs of the pushdown automaton, is first constructed in a forward procedure to determine which transitions are reachable, and then employed in a backward procedure to determine which of these transitions can lead to a final stat