# A Gray Code for the Ideals of a Forest Poset

@article{Koda1993AGC, title={A Gray Code for the Ideals of a Forest Poset}, author={Yasunori Koda and Frank Ruskey}, journal={J. Algorithms}, year={1993}, volume={15}, pages={324-340} }

Abstract We present two algorithms for listing all the ideals of a forest poset. These algorithms generate ideals in a gray code manner; that is, consecutive ideals differ by exactly one element. Both algorithms use storage O(n), where n is the number of elements in the poset. On each iteration, the first algorithm does a partial traversal of the current ideal being listed and runs in time O(nN), where N is the number of ideals of the poset. The second algorithm mimics the first, but it…

## Figures from this paper

## 39 Citations

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### IDEALS IN A FOREST, ONE-WAY INFINITE BINARY TREES AND THE CONTRACTION METHOD

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The analysis of an algorithm by Koda and Ruskey for listing ideals in a forest poset leads to a study of random binary trees and their limits as infinite random binary trees. The corresponding finite…

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This paper calculates loopless functional versions of the Gray code algorithm, the Koda-Ruskey algorithm for listing the prefixes of a forest, and the Johnson-Trotter algorithm for generating permutations.

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