Fall Chess Tourney

White to moveThrough I hadn’t played chess in over a year, I decided to enter this year’s office G15 tournament. Not surprisingly, I finished last (in the A bracket) with only a single draw in my column after 10 games. A couple games I lost quickly, but for most of them, I kept it close until I lost my patience and tried to make things happen.

Black to moveThe exception was this game (interactive player) in which I was a piece up as White, but ran out of time. In the first shown position I’ve already given Black the advantage with some minor mistakes, but he let me back in with Qd6. That allowed me to force his bishop back with f4 and then to fork the bishop and queen with e5 (second position). I got a bishop for two central pawns, and the computer rates the game as even. Black should have pushed his pawn to d3 with a discovered attack on my rook.

Black to moveBlack made good use of his passed center pawns, but ran out of steam when I seemed to have them immobilized (third diagram). Qd4 might have been a good move to try to kick my blockading queen and get his pawns moving again. Instead he tried some flank attacks with his rooks. Meanwhile I pushed my b pawn to remove his c pawn that was anchoring the central pawns and then I was able to put my extra piece to use and capture his menacing pawns.

White to moveAfter that, it was obvious I was going to run out of time, so Black played safe moves while I pointlessly made small gains, though I didn’t record the moves after the final shown position.

Fall Chess Round 4 Game 2

Black to moveAfter winning the first game, I was able to relax a little for the second game of the match. I played Black and quickly found myself getting bottled up in the diagrammed position. I decide to go in for the possibly-complicated trade with Nxe5. Post-game discussion revealed that White saw farther ahead than I did but not far enough. He expected to win material by having his pawn take at e5, f6 and e7 to threaten my queen while letting my bishop take at b5 and c1. With my queen threatened, I would have to give up the bishop, he thought. Luckily for me, I was able to use the newly opened file to exchange queens and rescue my bishop.

Black to moveAfter the smoke cleared, I had taken his rook and pawn at the cost of a knight. Not enough of an advantage for a clear win, but certainly an nice advantage, nonetheless. After some regrouping of pieces on both sides, White started to bring his king into the action to reach the next shown position. However, it turned out to be a blunder since the tactical reply Rd2+ won his bishop.

Black to moveNow I had a comfortable lead, and in the final diagram I found a move to improve my overall position while giving back a little material. After Rxc3 Rxc3, Bxe5 I was a piece up with three strong passed pawns, and Black soon resigned.

That gives me 4 wins, 4 losses and no draws for a solid third place out of five.

Fall Chess Round 4 Game 1

White to moveMy opponent for the fourth round had beat me twice in last year’s G15 tournament, but the games were close enough that I had hope of getting 1 out of 2 points and making a respectable showing in the A bracket.

I was White in the first game opening up with a Queen’s Gambit Declined with some early pawn action on the queenside to reach the first shown position. It looked like I could take the pawn at a5 with my rook, but I soon realized he was setting a trap for me.

Black to moveIf I took the pawn, he would take my bishop reveaing an attack on the rook. I calmly castled instead, and he traded bishops anyway.

I then started to put pressure on the a pawn. He decided to let me have it instead of getting all bottled up trying to defend it. Black can add a second defender to the pawn with Qd8, but I’m not sure he can add a third before I can add my queen as a third attacker. The pawn didn’t seem that valuable anyway since my extra pawn was doubled.

Black to moveAfter taking the pawn, we had a rook stand-off, and I took the opportunity to trade them all away since I often run into time trouble. After symmetrical knight invasions and threats, we reached the next position. Black could have traded knights while winning a pawn and leaving both sides with fractured pawn formations, but he had his sights on my king, thinking he might get a killer knight fork on f2.

White to moveHowever, the attack did not pan out, and after getting my knight back on the kingside to counter any further threats, I offered to trade queens before seeing a better use for my queen. Black refused to trade, and I had to offer again to get my queen back into position for the attack (this time I didn’t want him to take the trade). After he declined the trade again, we arrived at the next shown position. Now it was time for the attack.

White to moveWith his forces away, I was able to invade his king’s position starting with Qg6+. Taking two pawns gave me a strong position in the final diagram, but how to finish? With less than two minutes remaining on my clock, I was fortunate to see a combination to trade queens and win a pawn and knight to boot. After Qxc7+ Kxd7, Nxd5+ produced the fork to win back his queen. From there it was simple to promote pawns and win.

Fall Chess Round 3

White to moveI lost both of my round 3 games against another top player. In the first game, as White, I made the mistake of going after a pawn while leaving myself open for an invasion by Black’s queen. In the first diagrammed position I have the e4 pawn attacked twice while it’s defended once, but making the capture leaves my king exposed for an attack. I should have made a developing move instead, such as getting my bishop out to allow castling. (“First to castle, never hassled” was what the great Polinski used to chant.)

White to move The second position shows the quick penalty for my mistake. Not only is he going to get the pawn back, but I will lose more material, too. Luckily, Black didn’t find the very best moves, and I was able to parry the attack being down only a knight for a pawn. But further mistakes by me allowed him to quickly convert the advantage into a win.

White to moveI played Black in the second game, and my position looked pretty crummy coming out of the opening with two sets of doubled pawns, but I did have some hope for improvement. The extra f pawn could be used for attacking, I might coerce an exchange at c6 to undouble that pawn, and the rook might be able to attack on the half-open h file. The first two of those ideas came to pass, and I ended up with a favorable position after a few exchanges, as seen in the second diagram of this game, plus I had the “advantage” of two bishops vs. two knights.

Black to move Unfortunately, this is where I blundered, not noticing that the e7 pawn was attacked twice. Once he broke up the pawn chain, I couldn’t keep the remaining pawns all defended and soon lost.

Fall Chess Round 2

White to move Round 2 brought my first (and probably only) wins in the tournament. We played these games on Yahoo, which worked out well. (Not only does is keep time and record the game, but it also prevents me from making an illegal move, like moving into check.) I was White in the first game. Computer analysis questions almost every move on both sides, but I managed to go up a couple of pawns only to soon gave them back trying to simplify into an ending with strong central pawns. I didn’t go about it the best way, but the position shown is still winning with a nice passed pawn. Unfortunately, I goofed with e4, giving Black a chance to equalize with Ra3+, but he missed it, too, and I survived.

Black to Move In the second game, I got off to an comfortable lead by winning a pawn and the exchange (my bishop for his rook), but I panicked a little in the given position. I suddenly saw the mate threat with bishop at h6 and queen at g7. The only way out I could see was to give back the exchange by Re6 (my rook for his knight). Turns out I had time to take the knight with the pawn and still meet Bh6 with Bf8. For some reason, he didn’t take the rook, though I still would have been up three pawns. I was eventually able to simplify the position and use my material advantage to win.

In the Round 1 notes, I mentioned I was working on using a JavaScript game viewer. LT-PGN-VIEWER looked promising, but I decided it wasn’t as good as the older Java applet. So the round 1 games are now available with the Java applet viewer: Game 1, Game 2.

Fall Chess Round 1

Black to MoveFor the Fall chess tournament, we play two 15 minute games per match instead of one 30 minute game. I got bumped up to the A group this time and started out against the club’s strongest player. [I’m trying to set-up a JavaScript PGN player, but I don’t have that ready yet.] The first position is from late in the first game with me playing black. It’s black to move, what do you do? Most moves, including the one I picked lead to quick death, but there is one move that keeps the game going.

Black to MoveI played white in the second game and started out a little unusual by getting my queen out early and breaking up his fianchettoed bishop. I didn’t know if it was sound, but thought it best to do something strange since I don’t know openings that well and may fall into a trap. Computer analysis doesn’t show any problem with the position. Black was worried about a kingside attack and quickly arranged to trade queens. After more trading and a lost pawn, I ran out of time in a poor position with a knight and rook and a few scattered pawns.

Predictable Randomness

One GNU Chess source file I didn’t port to Java was the random number generator, and that turned out to be a problem for processing the binary opening book files.

The board position hash codes are 64-bit numbers created by xor’ing a set of hash codes that come from the random number generator. These hash codes are written to the binary book file, so in order to read a binary book file, you have to get the exact same sequence of “random” numbers from your random number generator. So I ported over the random number algorithm and was then able to read the binary book files which allows the program to play moves from the opening book.

I also got PGN file reading working, so I don’t know of any remaining functional issues (except for the i/o handling, especially control-C, which I may just ignore).

I tried the program on the 300 “Win at Chess” problems. The Java version got 278 correct, and the C version got 284 correct. Both used 5 seconds per move on my Mac G5.