diff -r -u -X .ignore gnugo-copy/engine/board.c gnugo/engine/board.c --- gnugo-copy/engine/board.c 2006-12-30 20:59:01.109375000 +0100 +++ gnugo/engine/board.c 2007-01-02 19:48:48.906250000 +0100 @@ -2,7 +2,7 @@ * This is GNU Go, a Go program. Contact gnugo@gnu.org, or see * * http://www.gnu.org/software/gnugo/ for more information. * * * - * Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005 and 2006 * + * Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 and 2007 * * by the Free Software Foundation. * * * * This program is free software; you can redistribute it and/or * @@ -1778,7 +1778,7 @@ liberties = string[str_nr].liberties; to_copy = maxlib > liberties ? liberties : maxlib; - if (liberties <= MAX_LIBERTIES || maxlib <= MAX_LIBERTIES) { + if (to_copy <= MAX_LIBERTIES) { /* The easy case, it suffices to copy liberty locations from the * incrementally updated list. */ diff -r -u -X .ignore gnugo-copy/engine/unconditional.c gnugo/engine/unconditional.c --- gnugo-copy/engine/unconditional.c 2006-12-30 21:48:42.703125000 +0100 +++ gnugo/engine/unconditional.c 2007-01-02 19:53:46.187500000 +0100 @@ -2,7 +2,7 @@ * This is GNU Go, a Go program. Contact gnugo@gnu.org, or see * * http://www.gnu.org/software/gnugo/ for more information. * * * - * Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005 and 2006 * + * Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 and 2007 * * by the Free Software Foundation. * * * * This program is free software; you can redistribute it and/or * @@ -41,7 +41,7 @@ { int other = OTHER_COLOR(color); int something_captured = 1; /* To get into the first turn of the loop. */ - int string_found = 0; + int invincible_found = 0; int moves_played = 0; int save_moves; int libs[MAXLIBS]; @@ -53,26 +53,20 @@ /* Nothing captured so far in this turn of the loop. */ something_captured = 0; - /* Is there something left to try to capture? */ - string_found = 0; + /* If we found any invincible string in this turn of the loop. */ + invincible_found = 0; /* Visit all friendly strings on the board. */ for (pos = BOARDMIN; pos < BOARDMAX; pos++) { - if (board[pos] != color || find_origin(pos) != pos) + if (board[pos] != color || find_origin(pos) != pos + || exceptions[pos]) continue; - if (exceptions && exceptions[pos]) - continue; - - string_found = 1; - /* Try to capture the string at pos. */ liberties = findlib(pos, MAXLIBS, libs); save_moves = moves_played; - for (k = 0; k < liberties; k++) { - if (trymove(libs[k], other, "unconditional_life", pos)) - moves_played++; - } + for (k = 0; k < liberties; k++) + moves_played += trymove(libs[k], other, "unconditional_life", pos); /* Successful if already captured or a single liberty remains. * Otherwise we must rewind and take back the last batch of moves. @@ -96,16 +90,19 @@ moves_played++; something_captured = 1; } - else + else { + invincible_found = 1; + while (moves_played > save_moves) { popgo(); moves_played--; } + } } } if (none_invincible) - *none_invincible = !string_found; + *none_invincible = !invincible_found; return moves_played; } @@ -148,15 +145,28 @@ * 4. Play an opponent stone anywhere it can get one empty * neighbor. (I.e. reduce two space eyes to one space eyes.) * - * Remaining opponent strings in atari and remaining liberties of the - * unconditionally alive strings constitute the unconditional - * territory. + * Remaining opponent strings in atari (and its only liberty) and + * remaining liberties of the unconditionally alive strings constitute + * the unconditional territory. * * Opponent strings from the initial position placed on * unconditional territory are unconditionally dead. * * - - - - - - - * + * Step 2 is done, because of such position (we have to extend a stone + * in atari before reducing an eyespace): + * + * OOXOO + * OX.XO + * OX.XO + * OXXXO + * OX.XO + * OXXXO + * OOOOO + * + * - - - - - - - + * * The deficiency with this algorithm is that a certain class of sekis * are considered as dead, e.g. this position: * @@ -183,7 +193,7 @@ * 1. Run algorithm 1. * 2. Return to the original position. * 3. Capture all capturable O strings which according to algorithm 1 - * do not belong to unconditional territory. + * do belong to unconditional territory. * 4. Play opponent stones on all liberties of the unconditionally * alive strings except where illegal. (That the move order may * determine exactly which liberties can be played legally is not @@ -197,9 +207,9 @@ * 9. Play an opponent stone anywhere it can get one empty * neighbor. (I.e. reduce two space eyes to one space eyes.) * - * Remaining opponent strings in atari and remaining liberties of the - * unconditionally alive strings constitute the unconditional - * territory. + * Remaining opponent strings in atari (and its only liberty) and + * remaining liberties of the unconditionally alive strings constitute + * the unconditional territory. * * Opponent strings from the initial position placed on * unconditional territory are unconditionally dead. @@ -263,8 +273,8 @@ * .OXXXOO * .OOOOO. * - * belong to different strings for the dead groups and to the same - * string for the seki groups. + * which belong to different strings for the dead groups and to the + * same string for the seki groups. * * The trick to avoid misclassifying areas where the opponent can form * a seki group but not an invincible group as unconditional territory @@ -296,9 +306,9 @@ * 10. Play an opponent stone anywhere it can get one empty * neighbor. (I.e. reduce two space eyes to one space eyes.) * - * Remaining opponent strings in atari and remaining liberties of the - * unconditionally alive strings constitute the unconditional - * territory. + * Remaining opponent strings in atari (and its only liberty) and + * remaining liberties of the unconditionally alive strings constitute + * the unconditional territory. * * Opponent strings from the initial position placed on * unconditional territory are unconditionally dead. @@ -313,7 +323,6 @@ void unconditional_life(int unconditional_territory[BOARDMAX], int color) { - int found_one; int other = OTHER_COLOR(color); int libs[MAXLIBS]; int liberties; @@ -335,6 +344,7 @@ int isolated = 1; int stones[2]; int pos2; + int checked_stone; if (board[pos] != color || find_origin(pos) != pos @@ -343,8 +353,9 @@ findstones(pos, 2, stones); for (k = 0; k < 2 && isolated; k++) { + checked_stone = stones[k]; for (r = 0; r < 8; r++) { - pos2 = stones[k] + delta[r]; + pos2 = checked_stone + delta[r]; if (!ON_BOARD(pos2) || (board[pos2] == color && !same_string(pos, pos2))) @@ -384,35 +395,30 @@ * alive strings except where illegal. */ for (pos = BOARDMIN; pos < BOARDMAX; pos++) { - if (board[pos] != color || potential_sekis[pos] || find_origin(pos) != pos) + if (board[pos] != color || find_origin(pos) != pos || potential_sekis[pos]) continue; /* Play as many liberties as we can. */ liberties = findlib(pos, MAXLIBS, libs); for (k = 0; k < liberties; k++) { - if (trymove(libs[k], other, "unconditional_life", pos)) - moves_played++; + moves_played += trymove(libs[k], other, "unconditional_life", pos); } } /* 2. Recursively extend opponent strings in atari, except where this * would be suicide. */ - found_one = 1; - while (found_one) { - /* Nothing found so far in this turn of the loop. */ - found_one = 0; - - for (pos = BOARDMIN; pos < BOARDMAX; pos++) { - if (board[pos] != other || countlib(pos) > 1) - continue; + for (pos = BOARDMIN; pos < BOARDMAX; pos++) { + if (board[pos] != other) + continue; - /* Try to extend the string at (m, n). */ + /* Try to extend the string. */ + while (countlib(pos) == 1) { findlib(pos, 1, libs); - if (trymove(libs[0], other, "unconditional_life", pos)) { + if (trymove(libs[0], other, "unconditional_life", pos)) moves_played++; - found_one = 1; - } + else + break; } } @@ -422,6 +428,8 @@ || board[pos] == EMPTY || find_origin(pos) != pos) continue; + + /* Try different rotations. */ for (r = 0; r < 4; r++) { int up = delta[r]; int right = delta[(r + 1) % 4]; @@ -432,15 +440,15 @@ continue; for (k = 0; k < 2; k++) { if (k == 1) - right = -right; + right = -right; /* Try a mirror reflection. */ if (board[pos + right] != EMPTY || board[pos + up - right] != EMPTY) continue; - if (board[pos - right] == EMPTY - && trymove(pos - right, other, "unconditional_life", pos)) - locally_played_moves++; - if (board[pos + up + right] == EMPTY - && trymove(pos + up + right, other, "unconditional_life", pos)) - locally_played_moves++; + if (board[pos - right] == EMPTY) + locally_played_moves += trymove(pos - right, other, + "unconditional_life", pos); + if (board[pos + up + right] == EMPTY) + locally_played_moves += trymove(pos + up + right, other, + "unconditional_life", pos); if (board[pos - right] == other && board[pos + up + right] == other && same_string(pos - right, pos + up + right)) { /* This is a critical seki. Extend the string with one stone @@ -450,8 +458,7 @@ popgo(); locally_played_moves--; } - trymove(pos - up, color, "unconditional_life", pos); - moves_played++; + moves_played += trymove(pos - up, color, "unconditional_life", pos); break; } else { @@ -472,13 +479,16 @@ continue; /* Play as many liberties as we can. */ liberties = findlib(pos, MAXLIBS, libs); - for (k = 0; k < liberties; k++) { - if (trymove(libs[k], other, "unconditional_life", pos)) - moves_played++; - } + for (k = 0; k < liberties; k++) + moves_played += trymove(libs[k], other, "unconditional_life", pos); } - + /* All opponent strings liberties are now inside opponent territory + (due to step 4.). If any string has 3 or more liberties, it is alive + (2 eyes can be made). If a string has 1 liberty it must be in atari, so + is dead (because we tried to extend strings in atari in step 5.). We + only have to check strings, which have 2 liberties. This operations + are made instead 9. and 10. step of the algorithm. */ for (pos = BOARDMIN; pos < BOARDMAX; pos++) { int apos; int bpos; @@ -493,11 +503,12 @@ continue; /* Only two liberties and these are adjacent. Play one. We want - * to maximize the number of open liberties. In this particular - * situation we can count this with approxlib for the opposite - * color. If the number of open liberties is the same, we - * maximize the total number of obtained liberties. - * Two relevant positions: + * to maximize the number of neighboring liberties (to split an + * eyespace). In this particular situation we can count this with + * approxlib for the opposite color. If the number of neighboring + * liberties is the same, we maximize the total number of obtained + * liberties. Two relevant positions (we want to make 2 eyes for + * these O groups): * * |XXX. * |OOXX |XXXXXXX @@ -510,14 +521,10 @@ alib = approxlib(apos, other, 4, NULL); blib = approxlib(bpos, other, 4, NULL); - if (aopen > bopen || (aopen == bopen && alib >= blib)) { - trymove(apos, other, "unconditional_life", pos); - moves_played++; - } - else { - trymove(bpos, other, "unconditional_life", pos); - moves_played++; - } + if (aopen > bopen || (aopen == bopen && alib >= blib)) + moves_played += trymove(apos, other, "unconditional_life", pos); + else + moves_played += trymove(bpos, other, "unconditional_life", pos); } /* Identify unconditionally alive stones and unconditional territory. */ @@ -532,8 +539,10 @@ } else if (board[pos] == other && countlib(pos) == 1) { unconditional_territory[pos] = 2; - findlib(pos, 1, libs); - unconditional_territory[libs[0]] = 2; + if (find_origin(pos) == pos) { + findlib(pos, 1, libs); + unconditional_territory[libs[0]] = 2; + } } } diff -r -u -X .ignore gnugo-copy/engine/worm.c gnugo/engine/worm.c --- gnugo-copy/engine/worm.c 2006-12-31 17:20:32.093750000 +0100 +++ gnugo/engine/worm.c 2007-01-02 20:02:58.859375000 +0100 @@ -2,7 +2,7 @@ * This is GNU Go, a Go program. Contact gnugo@gnu.org, or see * * http://www.gnu.org/software/gnugo/ for more information. * * * - * Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005 and 2006 * + * Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 and 2007 * * by the Free Software Foundation. * * * * This program is free software; you can redistribute it and/or * @@ -712,6 +712,7 @@ for (color = WHITE; color <= BLACK; color++) { unconditional_life(unconditional_territory, color); + gg_assert(stackp == 0); for (pos = BOARDMIN; pos < BOARDMAX; pos++) { if (!ON_BOARD(pos) || !unconditional_territory[pos]) @@ -732,7 +733,6 @@ worm[pos].unconditional_status = DEAD; } } - gg_assert(stackp == 0); } /*