Madlab comes with a collection of 997 capture problems (tesuji). These are basically unsorted regarding difficulty (however, they tend to get harder the higher the number is). The problems can be downloaded separately free of charge, and illustrate the kinds of problems the current version of MadLab is aimed at.

The problems are realistic in the sense that all (but a couple) of them are extracted from real dan- or pro-level games. The extracted problems have not been tampered with in any way -- each of them has appeared in an actual game excactly as it is (except that superflous stones have been removed). Please bear in mind, however, that these problems ask for a specific goal to be obtained (capturing blocks of stones), ignoring the general context of the game. In the middle-game such a capture may not be worthwhile, but even so, the problem may still have some merit as an endgame tesuji.

The problems do not approach the same overall high quality as, e.g., the ones in James Davies: Tesuji or Kano Yoshinori: Graded Go Problems for Beginners. But still quite a lot of them are amusing, and they illustrate the kinds of problems that tend to come up in real games. Hence, they may be of general interest to Go players and Go programmers, and for these purposes the problems can be freely distributed, provided that the source (MadLab) is acknowledged, and the notice in the sgf files is preserved. The problems may not be used commercially without the written consent of the author of MadLab.

  Download the problems as a zip file (~420 KB)

Each sgf file inludes a solution (verified by MadLab, which can solve all of these problems pretty quickly). Some of the problems may have multiple solutions, so there is no guarantee that the MadLab solution is unique (or the most efficient way to capture the stone(s)). The problems do not depend on ko, so the attacker is able to capture the stone(s) even if the defender should have an infinite supply of external ko threats.

The problems are included when you download MadLab (see File --> Open problems...), and can be played through with the MadLab solver (right-click on a block of stones and choose 'Capture' or 'Capture 1 of 2'). In the MadLab environment, you may try any kinds of defensive moves and MadLab will refute them, but alternatively the problems can be viewed in any Go program with sgf reading capability, like for instance SmartGo or Many Faces.

If anyone should have the time to sort the problems by difficulty or extract a 'best of' subset of them (or comment on the individual problems), I would only be happy to hear more and distribute such a collection here as well. I would also be interested in hearing about alternative solutions to any of the problems (i.e., solutions different from the one given in the sgf file).