The Complexity of Some Problems on Subsequences and Supersequences

  title={The Complexity of Some Problems on Subsequences and Supersequences},
  author={David Maier},
  journal={J. ACM},
  • D. Maier
  • Published 1 April 1978
  • Computer Science
  • J. ACM
The complexity of finding the Longest Common Subsequence (LCS) and the Shortest Common Supersequence (SCS) of an arbRrary number of sequences IS considered We show that the yes/no version of the LCS problem is NP-complete for sequences over an alphabet of size 2, and that the yes/no SCS problem is NPcomplete for sequences over an alphabet of size 5 

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