In computer science and operations research, exact algorithms are algorithms that always solve an optimization problem to optimality.
Unless P = NP, an exact algorithm for an NP-hard optimization problem cannot run in worst-case polynomial time. There has been extensive research on finding exact algorithms whose running time is exponential with a low base.
See also
- Approximation-preserving reduction
- APX is the class of problems with some constant-factor approximation algorithm
- Heuristic algorithm
- PTAS - a type of approximation algorithm that takes the approximation ratio as a parameter
References
- Fomin, Fedor V.; Kaski, Petteri (March 2013), "Exact Exponential Algorithms", Communications of the ACM, 56 (3): 80–88, doi:10.1145/2428556.2428575.
- Fomin, Fedor V.; Kratsch, Dieter (2010). Exact Exponential Algorithms. Springer. p. 203. ISBN 978-3-642-16532-0.