These instances are complete graphs with euclidian distances. They were converted by Ralf Borndörfer and Carlos Ferreira from TSPLIB problems, by selecting some nodes as Terminals.

*berlin52* is made out of 52 sights in Berlin.

*brazil58* are 58 cities in Brazil with the provincial capitals as
terminals.

*world666* are 666 cities around the world with the capitals
as terminals.

More information can be found among others in KM98 and PD00 .

The files can be found in the download section.

Name | |V| | |E| | |T| | DC | Opt |
---|---|---|---|---|---|

berlin52 | 52 | 1326 | 16 | Ps | 1044 |

brasil58 | 58 | 1653 | 25 | Ps | 13655 |

world666 | 666 | 221445 | 174 | Ps | 122467 |

The column **DC** classifies the difficulty of the instance.

- L
- Solvable by usage of local preprocessing. Typical examples are the SD-Test, BD-n Tests and FST computations. Neither a global upper nor lower bound needs to be computed.
- P
- Solvable by polynomial time algorithms, like dual ascent in combination with primal heuristic, a integral LP formulation or advanced preprocessing like reduced cost criteria or the RCR-Test.
- NP
- No polynomial time algorithm is known. Use of an exponential time enumeration sceme like Branch-and-Bound is neccessary.

The letter after class gives an impression how long it takes to solve
the problem using state-of-the-art soft- and hardware.
**s**ecounds means less than a minute (this includes
instances which can be solved in fractions of a second).
**m**inutes means less than an hour. **h**ours is less than a
day and **d**ays is less than a week. **w**eeks mean it takes
really a long time to solve this instance.
**?** means the instance is not solved or the time is not known.

If the number in the **Opt** column is written in *italics*
the optimum is not known. The number given is the best know upper bound.

Last Update : 2015/02/11 11:57:20 $ by Thorsten Koch

© 2001 by Konrad-Zuse-Zentrum für Informationstechnik Berlin (ZIB)

URL: http://www.zib.de