A Deterministic Two-Way Multi-head Finite Automaton Can Be Converted into a Reversible One with the Same Number of Heads
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On Stateless Multihead Finite Automata and Multihead Pushdown Automata
A stateless k-head two-way deterministic finite automaton (k-head 2DFA), has only one state, hence the designation stateless. Its transitions depends solely on the symbols currently scanned by its k heads, and in every such transition each head can move one cell left, right, or remain stationary. An input, which is delimited by end markers, is accepted if the machine, when started with all head...
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