The DOI matches its Crossref record; 1 of the 1 references it cites were found in a registry or an index.
On the complexity of time table and multi-commodity flow problems
Abstract
A very primitive version of Gotlieb's timetable problem is shown to be NP-complete, and therefore all the common timetable problems are NP-complete. A polynomial time algorithm, in case all teachers are binary, is shown. The theorem that a meeting function always exists if all teachers and classes have no time constraints is proved. The multi-commodity integral flow problem is shown to be NP-complete even if the number of commodities is two. This is true both in the directed and undirected cases. Finally, the two commodity real flow problem in undirected graphs is shown to be solvable in polynomial time. The time bound is O(|v|2|E|).
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Cites
The complexity of theorem-proving procedures
Cook, S. A. (1971) · Proceedings of the third annual ACM symposium on Theory of computing - STOC '71 · doi:10.1145/800157.805047 · Cited by 6,385
Cited by
(2010) · doi:10.5555/1855711.1855728 · Cited by 970
A linear-time algorithm for testing the truth of certain quantified boolean formulas
Aspvall, B., Plass, M. F., & Tarjan, R. E. (1979) · Information Processing Letters · doi:10.1016/0020-0190(79)90002-4 · Cited by 892
Quantum Hamiltonian Complexity
Gharibian, S., Huang, Y., Landau, Z., & Shin, S. W. (2015) · Foundations and Trends® in Theoretical Computer Science · doi:10.1561/0400000066 · Cited by 144
Metadata
- Authors
- Even, S., Itai, A., & Shamir, A.
- Venue
- 16th Annual Symposium on Foundations of Computer Science (sfcs 1975)
- Publisher
- IEEE
- Published
- 1975-10
- Pages
- 184-193
- ISSN
- 0272-5428 (ISSN-L)
- OpenAlex
- W2006146932
- Cited by
- 431
- References
- 1
- FWCI
- 1.38
- Type
- conference paper
- Language
- en
- Open access
- closed
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- CoChat. (2026). Citation check: On the complexity of time table and multi-commodity flow problems. https://app.cochat.ai/papers/10.1109/sfcs.1975.21
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- Even, S., Itai, A., & Shamir, A. (1975). On the complexity of time table and multi-commodity flow problems. 16th Annual Symposium on Foundations of Computer Science (sfcs 1975). https://doi.org/10.1109/sfcs.1975.21
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