A Gray Code for the Ideals of a Forest Poset

  title={A Gray Code for the Ideals of a Forest Poset},
  author={Yasunori Koda and Frank Ruskey},
  journal={J. Algorithms},
  • Y. Koda, F. Ruskey
  • Published 1 September 1993
  • Computer Science, Mathematics
  • J. Algorithms
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… 

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