Efficient coroutine generation of constrained Gray sequences

Donald E. Knuth; Frank Ruskey

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arXiv · cs/0404058

Efficient coroutine generation of constrained Gray sequences

Donald E. Knuth·Frank Ruskey

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Abstract

We study an interesting family of cooperating coroutines, which is able to generate all patterns of bits that satisfy certain fairly general ordering constraints, changing only one bit at a time. (More precisely, the directed graph of constraints is required to be cycle-free when it is regarded as an undirected graph.) If the coroutines are implemented carefully, they yield an algorithm that needs only a bounded amount of computation per bit change, thereby solving an open problem in the field of combinatorial pattern generation.

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Donald E. Knuth, Frank Ruskey. 2004-04-30. Efficient coroutine generation of constrained Gray sequences. https://arxiv.org/abs/cs/0404058

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