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[/] [connect-6/] [trunk/] [CONNECTK/] [connectk-2.0/] [src/] [ai/] [threats.c] - Blame information for rev 3

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/*
 
connectk -- a program to play the connect-k family of games
Copyright (C) 2007 Michael Levin
 
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
 
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
 
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 
*/
 
#include "config.h"
#include <math.h>
#include <glib.h>
#include "../shared.h"
 
/* Bits per threat level */
#define BITS_PER_THREAT 6
 
/* All threat functions work on this board */
static Board *b = NULL;
 
/* This is the line of threats currently being processed */
static struct {
        int threat[2];
        PIECE turn[2];
} line[MAX_BOARD_SIZE];
 
/* Running tally of threats for both players */
static int threat_counts[MAX_CONNECT_K + 1][2];
 
static AIWEIGHT threat_bits(int threat, PIECE type)
/* Bit pack the threat value */
{
        if (threat < 1)
                return 0;
 
        /* No extra value for building sequences over k - p unless it is
           enough to win */
        if (b->turn == type && connect_k - threat <= b->moves_left)
                threat = connect_k - place_p + 1;
        else if (threat >= connect_k - place_p)
                threat = connect_k - place_p - (type == b->turn);
 
        return 1 << ((threat - 1) * BITS_PER_THREAT);
}
 
static void threat_mark(int i, int threat, PIECE type)
{
        int j, index = 0;
 
        if (threat <= 0)
                return;
 
        /* No extra value for building sequences over k - p unless it is
           enough to win */
        if (b->turn == type && connect_k - threat <= b->moves_left)
                threat = connect_k - place_p + 1;
        else if (threat >= connect_k - place_p)
                threat = connect_k - place_p - (type == b->turn);
 
        /* Do not mark if this threat is dominated by a preceeding threat;
           Likewise supress any smaller threats */
        for (j = i; j >= 0 && j > i - connect_k; j--)
                if (line[j].threat[0] > threat)
                        return;
                else if (line[j].threat[0] < threat) {
                        line[j].threat[0] = 0;
                        line[j].threat[1] = 0;
                }
 
        /* Store up to two threats per tile in the line */
        if (line[i].threat[index])
                index++;
        line[i].threat[index] = threat;
        line[i].turn[index] = type;
}
 
static int threat_window(int x, int y, int dx, int dy,
                         PIECE *ptype, int *pdouble)
{
        int min, max, count = 0;
        PIECE p, type = PIECE_NONE;
 
        /* Check if this tile is empty */
        p = piece_at(b, x, y);
        if (!piece_empty(p))
                return 0;
 
        /* Push forward the max and find the window type */
        for (max = 1; max < connect_k; max++) {
                p = piece_at(b, x + dx * max, y + dy * max);
                if (p == PIECE_ERROR)
                        break;
                if (!piece_empty(p)) {
                        if (type == PIECE_NONE)
                                type = p;
                        else if (type != p)
                                break;
                        count++;
                }
        }
        max--;
 
        /* Try to push the entire window back */
        for (min = -1; min > -connect_k; min--) {
                p = piece_at(b, x + dx * min, y + dy * min);
                if (p == PIECE_ERROR || piece_empty(p))
                        break;
                if (type == PIECE_NONE)
                        type = p;
                else if (type != p)
                        break;
                if (max - min > connect_k - 1) {
                        p = piece_at(b, x + dx * max, y + dy * max);
                        if (p == type)
                                count--;
                        max--;
                }
                count++;
        }
        min++;
 
        /* Push back min if we haven't formed a complete window, this window
           can't be a double */
        if (max - min < connect_k - 1) {
                for (min--; min > max - connect_k; min--) {
                        p = piece_at(b, x + dx * min, y + dy * min);
                        if (p == PIECE_ERROR)
                                break;
                        if (!piece_empty(p)) {
                                if (type != p)
                                        break;
                                if (type == PIECE_NONE)
                                        type = p;
                                count++;
                        }
                }
                *pdouble = 0;
                min++;
        }
 
        *ptype = type;
        if (max - min >= connect_k - 1)
                return count;
        return 0;
}
 
static AIWEIGHT threat_line(int x, int y, int dx, int dy)
{
        int i;
        AIWEIGHT weight = 0;
 
        /* Mark the maximum threat for each */
        for (i = 0; x >= 0 && x < board_size && y >= 0 && y < board_size; i++) {
                int count[2], tmp, double_threat = 1;
                PIECE type[2];
 
                count[0] = threat_window(x, y, dx, dy, type, &double_threat);
                count[1] = threat_window(x, y, -dx, -dy, type + 1,
                                         &double_threat);
                if (count[1] > count[0]) {
                        tmp = count[1];
                        count[1] = count[0];
                        count[0] = tmp;
                        tmp = type[1];
                        type[1] = type[0];
                        type[0] = tmp;
                }
                line[i].threat[0] = 0;
                line[i].threat[1] = 0;
                threat_mark(i, count[0], type[0]);
                if (double_threat)
                        threat_mark(i, count[1], type[1]);
                x += dx;
                y += dy;
        }
 
        /* Commit stored line values to the board */
        x -= dx;
        y -= dy;
        for (i--; x >= 0 && x < board_size && y >= 0 && y < board_size; i--) {
                AIWEIGHT bits[2];
                PIECE p;
 
                bits[0] = threat_bits(line[i].threat[0], line[i].turn[0]);
                bits[1] = threat_bits(line[i].threat[1], line[i].turn[1]);
                p = piece_at(b, x, y);
                if (piece_empty(p) && line[i].threat[0]) {
                        threat_counts[line[i].threat[0]][line[i].turn[0] - 1]++;
                        if (line[i].threat[1])
                                threat_counts[line[i].threat[1]]
                                             [line[i].turn[1] - 1]++;
                        if (p >= PIECE_THREAT0)
                                place_threat(b, x, y, p - PIECE_THREAT0 +
                                             bits[0] + bits[1]);
                        else
                                place_threat(b, x, y, bits[0] + bits[1]);
                }
                if (b->turn != line[i].turn[0])
                        bits[0] = -bits[0];
                if (b->turn != line[i].turn[1])
                        bits[1] = -bits[1];
                weight += bits[0] + bits[1];
                x -= dx;
                y -= dy;
        }
 
        return weight;
}
 
AIMoves *ai_threats(const Board *original)
{
        AIMoves *moves;
        AIWEIGHT u_sum = 0;
        int i;
 
        b = board_new();
        board_copy(original, b);
 
        /* Clear threat tallys */
        for (i = 0; i < connect_k; i++) {
                threat_counts[i][0] = 0;
                threat_counts[i][1] = 0;
        }
 
        /* Horizontal lines */
        for (i = 0; i < board_size; i++)
                u_sum += threat_line(0, i, 1, 0);
 
        /* Vertical lines */
        for (i = 0; i < board_size; i++)
                u_sum += threat_line(i, 0, 0, 1);
 
        /* SE diagonals */
        for (i = 0; i < board_size - connect_k + 1; i++)
                u_sum += threat_line(i, 0, 1, 1);
        for (i = 1; i < board_size - connect_k + 1; i++)
                u_sum += threat_line(0, i, 1, 1);
 
        /* SW diagonals */
        for (i = connect_k - 1; i < board_size; i++)
                u_sum += threat_line(i, 0, -1, 1);
        for (i = 1; i < board_size - connect_k + 1; i++)
                u_sum += threat_line(board_size - 1, i, -1, 1);
 
        moves = ai_marks(b, PIECE_THREAT(1));
        moves->utility = u_sum;
        board_free(b);
        return moves;
}
 
void debug_counts(void)
{
        int i, sum = 0;
 
        if (!b)
                return;
 
        g_debug("Threat counts (black, white):");
        for (i = 1; i < connect_k; i++) {
                g_debug("%d: %3d %3d", i, threat_counts[i][0],
                        threat_counts[i][1]);
                sum += threat_counts[i][0] * threat_bits(i, b->turn) -
                       threat_counts[i][1] *
                       threat_bits(i, other_player(b->turn));
        }
        if (sum > 0)
                g_debug("Threat sum: %d (10^%.2f)", sum, log10((double)sum));
        else if (sum < 0)
                g_debug("Threat sum: %d (-10^%.2f)", sum, log10((double)-sum));
        else
                g_debug("Threat sum: 0");
}
 
static int threat_number(int player, int threat)
{
        return threat_counts[threat][player] / (connect_k - threat);
}
 
AIMoves *ai_priority(const Board *b)
{
        AIMoves *moves;
        int i, j, stage[2] = {1, 1}, mask, bits;
 
        moves = ai_threats(b);
 
        /* Do not prioritize if we've won */
        if (threat_counts[connect_k - place_p + 1][b->turn - 1]) {
                moves->utility = AIW_WIN;
                return moves;
        }
 
        /* Find the largest supported threat for each player */
        for (i = 2; i < connect_k; i++) {
                if (threat_number(0, i - 1) >= place_p &&
                    threat_number(0, i) > place_p)
                        stage[0] = i;
                if (threat_number(1, i - 1) >= place_p &&
                    threat_number(1, i) > place_p)
                        stage[1] = i;
        }
 
        if (opt_debug_stage)
                g_debug("Stages %d/%d", stage[0], stage[1]);
 
        /* Do not prioritize if we're losing */
        if (stage[b->turn - 1] <= stage[other_player(b->turn) - 1]) {
                moves->utility = -stage[other_player(b->turn) - 1];
                return moves;
        }
 
        /* Threats above the player's stage are no more valuable than the
           stage */
        bits = 1 << (stage[b->turn - 1] * BITS_PER_THREAT);
        mask = bits - 1;
        for (i = 0; i < moves->len; i++) {
                AIWEIGHT w = moves->data[i].weight, w2;
 
                if (w < AIW_THREAT_MAX && w >= bits) {
                        w2 = w & mask;
                        w = w & ~mask;
                        for (j = stage[b->turn - 1];
                             w && j < connect_k - place_p + 1; j++) {
                                w = w >> BITS_PER_THREAT;
                                w2 += w & mask;
                        }
                        moves->data[i].weight = w2;
                }
        }
 
        /* Stage determines weight */
        moves->utility = stage[b->turn - 1];
        return moves;
}

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Subversion Repositories connect-6

[/] [connect-6/] [trunk/] [CONNECTK/] [connectk-2.0/] [src/] [ai/] [threats.c] - Blame information for rev 3

Line No.	Rev	Author	Line
1	3	sumanta.ch
2			`/*`
3
4			`connectk -- a program to play the connect-k family of games`
5			`Copyright (C) 2007 Michael Levin`
6
7			`This program is free software; you can redistribute it and/or`
8			`modify it under the terms of the GNU General Public License`
9			`as published by the Free Software Foundation; either version 2`
10			`of the License, or (at your option) any later version.`
11
12			`This program is distributed in the hope that it will be useful,`
13			`but WITHOUT ANY WARRANTY; without even the implied warranty of`
14			`MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the`
15			`GNU General Public License for more details.`
16
17			`You should have received a copy of the GNU General Public License`
18			`along with this program; if not, write to the Free Software`
19			`Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.`
20
21			`*/`
22
23			`#include "config.h"`
24			`#include <math.h>`
25			`#include <glib.h>`
26			`#include "../shared.h"`
27
28			`/* Bits per threat level */`
29			`#define BITS_PER_THREAT 6`
30
31			`/* All threat functions work on this board */`
32			`static Board *b = NULL;`
33
34			`/* This is the line of threats currently being processed */`
35			`static struct {`
36			`int threat[2];`
37			`PIECE turn[2];`
38			`} line[MAX_BOARD_SIZE];`
39
40			`/* Running tally of threats for both players */`
41			`static int threat_counts[MAX_CONNECT_K + 1][2];`
42
43			`static AIWEIGHT threat_bits(int threat, PIECE type)`
44			`/* Bit pack the threat value */`
45			`{`
46			`if (threat < 1)`
47			`return 0;`
48
49			`/* No extra value for building sequences over k - p unless it is`
50			`enough to win */`
51			`if (b->turn == type && connect_k - threat <= b->moves_left)`
52			`threat = connect_k - place_p + 1;`
53			`else if (threat >= connect_k - place_p)`
54			`threat = connect_k - place_p - (type == b->turn);`
55
56			`return 1 << ((threat - 1) * BITS_PER_THREAT);`
57			`}`
58
59			`static void threat_mark(int i, int threat, PIECE type)`
60			`{`
61			`int j, index = 0;`
62
63			`if (threat <= 0)`
64			`return;`
65
66			`/* No extra value for building sequences over k - p unless it is`
67			`enough to win */`
68			`if (b->turn == type && connect_k - threat <= b->moves_left)`
69			`threat = connect_k - place_p + 1;`
70			`else if (threat >= connect_k - place_p)`
71			`threat = connect_k - place_p - (type == b->turn);`
72
73			`/* Do not mark if this threat is dominated by a preceeding threat;`
74			`Likewise supress any smaller threats */`
75			`for (j = i; j >= 0 && j > i - connect_k; j--)`
76			`if (line[j].threat[0] > threat)`
77			`return;`
78			`else if (line[j].threat[0] < threat) {`
79			`line[j].threat[0] = 0;`
80			`line[j].threat[1] = 0;`
81			`}`
82
83			`/* Store up to two threats per tile in the line */`
84			`if (line[i].threat[index])`
85			`index++;`
86			`line[i].threat[index] = threat;`
87			`line[i].turn[index] = type;`
88			`}`
89
90			`static int threat_window(int x, int y, int dx, int dy,`
91			`PIECE ptype, int pdouble)`
92			`{`
93			`int min, max, count = 0;`
94			`PIECE p, type = PIECE_NONE;`
95
96			`/* Check if this tile is empty */`
97			`p = piece_at(b, x, y);`
98			`if (!piece_empty(p))`
99			`return 0;`
100
101			`/* Push forward the max and find the window type */`
102			`for (max = 1; max < connect_k; max++) {`
103			`p = piece_at(b, x + dx * max, y + dy * max);`
104			`if (p == PIECE_ERROR)`
105			`break;`
106			`if (!piece_empty(p)) {`
107			`if (type == PIECE_NONE)`
108			`type = p;`
109			`else if (type != p)`
110			`break;`
111			`count++;`
112			`}`
113			`}`
114			`max--;`
115
116			`/* Try to push the entire window back */`
117			`for (min = -1; min > -connect_k; min--) {`
118			`p = piece_at(b, x + dx * min, y + dy * min);`
119			`if (p == PIECE_ERROR \|\| piece_empty(p))`
120			`break;`
121			`if (type == PIECE_NONE)`
122			`type = p;`
123			`else if (type != p)`
124			`break;`
125			`if (max - min > connect_k - 1) {`
126			`p = piece_at(b, x + dx * max, y + dy * max);`
127			`if (p == type)`
128			`count--;`
129			`max--;`
130			`}`
131			`count++;`
132			`}`
133			`min++;`
134
135			`/* Push back min if we haven't formed a complete window, this window`
136			`can't be a double */`
137			`if (max - min < connect_k - 1) {`
138			`for (min--; min > max - connect_k; min--) {`
139			`p = piece_at(b, x + dx * min, y + dy * min);`
140			`if (p == PIECE_ERROR)`
141			`break;`
142			`if (!piece_empty(p)) {`
143			`if (type != p)`
144			`break;`
145			`if (type == PIECE_NONE)`
146			`type = p;`
147			`count++;`
148			`}`
149			`}`
150			`*pdouble = 0;`
151			`min++;`
152			`}`
153
154			`*ptype = type;`
155			`if (max - min >= connect_k - 1)`
156			`return count;`
157			`return 0;`
158			`}`
159
160			`static AIWEIGHT threat_line(int x, int y, int dx, int dy)`
161			`{`
162			`int i;`
163			`AIWEIGHT weight = 0;`
164
165			`/* Mark the maximum threat for each */`
166			`for (i = 0; x >= 0 && x < board_size && y >= 0 && y < board_size; i++) {`
167			`int count[2], tmp, double_threat = 1;`
168			`PIECE type[2];`
169
170			`count[0] = threat_window(x, y, dx, dy, type, &double_threat);`
171			`count[1] = threat_window(x, y, -dx, -dy, type + 1,`
172			`&double_threat);`
173			`if (count[1] > count[0]) {`
174			`tmp = count[1];`
175			`count[1] = count[0];`
176			`count[0] = tmp;`
177			`tmp = type[1];`
178			`type[1] = type[0];`
179			`type[0] = tmp;`
180			`}`
181			`line[i].threat[0] = 0;`
182			`line[i].threat[1] = 0;`
183			`threat_mark(i, count[0], type[0]);`
184			`if (double_threat)`
185			`threat_mark(i, count[1], type[1]);`
186			`x += dx;`
187			`y += dy;`
188			`}`
189
190			`/* Commit stored line values to the board */`
191			`x -= dx;`
192			`y -= dy;`
193			`for (i--; x >= 0 && x < board_size && y >= 0 && y < board_size; i--) {`
194			`AIWEIGHT bits[2];`
195			`PIECE p;`
196
197			`bits[0] = threat_bits(line[i].threat[0], line[i].turn[0]);`
198			`bits[1] = threat_bits(line[i].threat[1], line[i].turn[1]);`
199			`p = piece_at(b, x, y);`
200			`if (piece_empty(p) && line[i].threat[0]) {`
201			`threat_counts[line[i].threat[0]][line[i].turn[0] - 1]++;`
202			`if (line[i].threat[1])`
203			`threat_counts[line[i].threat[1]]`
204			`[line[i].turn[1] - 1]++;`
205			`if (p >= PIECE_THREAT0)`
206			`place_threat(b, x, y, p - PIECE_THREAT0 +`
207			`bits[0] + bits[1]);`
208			`else`
209			`place_threat(b, x, y, bits[0] + bits[1]);`
210			`}`
211			`if (b->turn != line[i].turn[0])`
212			`bits[0] = -bits[0];`
213			`if (b->turn != line[i].turn[1])`
214			`bits[1] = -bits[1];`
215			`weight += bits[0] + bits[1];`
216			`x -= dx;`
217			`y -= dy;`
218			`}`
219
220			`return weight;`
221			`}`
222
223			`AIMoves ai_threats(const Board original)`
224			`{`
225			`AIMoves *moves;`
226			`AIWEIGHT u_sum = 0;`
227			`int i;`
228
229			`b = board_new();`
230			`board_copy(original, b);`
231
232			`/* Clear threat tallys */`
233			`for (i = 0; i < connect_k; i++) {`
234			`threat_counts[i][0] = 0;`
235			`threat_counts[i][1] = 0;`
236			`}`
237
238			`/* Horizontal lines */`
239			`for (i = 0; i < board_size; i++)`
240			`u_sum += threat_line(0, i, 1, 0);`
241
242			`/* Vertical lines */`
243			`for (i = 0; i < board_size; i++)`
244			`u_sum += threat_line(i, 0, 0, 1);`
245
246			`/* SE diagonals */`
247			`for (i = 0; i < board_size - connect_k + 1; i++)`
248			`u_sum += threat_line(i, 0, 1, 1);`
249			`for (i = 1; i < board_size - connect_k + 1; i++)`
250			`u_sum += threat_line(0, i, 1, 1);`
251
252			`/* SW diagonals */`
253			`for (i = connect_k - 1; i < board_size; i++)`
254			`u_sum += threat_line(i, 0, -1, 1);`
255			`for (i = 1; i < board_size - connect_k + 1; i++)`
256			`u_sum += threat_line(board_size - 1, i, -1, 1);`
257
258			`moves = ai_marks(b, PIECE_THREAT(1));`
259			`moves->utility = u_sum;`
260			`board_free(b);`
261			`return moves;`
262			`}`
263
264			`void debug_counts(void)`
265			`{`
266			`int i, sum = 0;`
267
268			`if (!b)`
269			`return;`
270
271			`g_debug("Threat counts (black, white):");`
272			`for (i = 1; i < connect_k; i++) {`
273			`g_debug("%d: %3d %3d", i, threat_counts[i][0],`
274			`threat_counts[i][1]);`
275			`sum += threat_counts[i][0] * threat_bits(i, b->turn) -`
276			`threat_counts[i][1] *`
277			`threat_bits(i, other_player(b->turn));`
278			`}`
279			`if (sum > 0)`
280			`g_debug("Threat sum: %d (10^%.2f)", sum, log10((double)sum));`
281			`else if (sum < 0)`
282			`g_debug("Threat sum: %d (-10^%.2f)", sum, log10((double)-sum));`
283			`else`
284			`g_debug("Threat sum: 0");`
285			`}`
286
287			`static int threat_number(int player, int threat)`
288			`{`
289			`return threat_counts[threat][player] / (connect_k - threat);`
290			`}`
291
292			`AIMoves ai_priority(const Board b)`
293			`{`
294			`AIMoves *moves;`
295			`int i, j, stage[2] = {1, 1}, mask, bits;`
296
297			`moves = ai_threats(b);`
298
299			`/* Do not prioritize if we've won */`
300			`if (threat_counts[connect_k - place_p + 1][b->turn - 1]) {`
301			`moves->utility = AIW_WIN;`
302			`return moves;`
303			`}`
304
305			`/* Find the largest supported threat for each player */`
306			`for (i = 2; i < connect_k; i++) {`
307			`if (threat_number(0, i - 1) >= place_p &&`
308			`threat_number(0, i) > place_p)`
309			`stage[0] = i;`
310			`if (threat_number(1, i - 1) >= place_p &&`
311			`threat_number(1, i) > place_p)`
312			`stage[1] = i;`
313			`}`
314
315			`if (opt_debug_stage)`
316			`g_debug("Stages %d/%d", stage[0], stage[1]);`
317
318			`/* Do not prioritize if we're losing */`
319			`if (stage[b->turn - 1] <= stage[other_player(b->turn) - 1]) {`
320			`moves->utility = -stage[other_player(b->turn) - 1];`
321			`return moves;`
322			`}`
323
324			`/* Threats above the player's stage are no more valuable than the`
325			`stage */`
326			`bits = 1 << (stage[b->turn - 1] * BITS_PER_THREAT);`
327			`mask = bits - 1;`
328			`for (i = 0; i < moves->len; i++) {`
329			`AIWEIGHT w = moves->data[i].weight, w2;`
330
331			`if (w < AIW_THREAT_MAX && w >= bits) {`
332			`w2 = w & mask;`
333			`w = w & ~mask;`
334			`for (j = stage[b->turn - 1];`
335			`w && j < connect_k - place_p + 1; j++) {`
336			`w = w >> BITS_PER_THREAT;`
337			`w2 += w & mask;`
338			`}`
339			`moves->data[i].weight = w2;`
340			`}`
341			`}`
342
343			`/* Stage determines weight */`
344			`moves->utility = stage[b->turn - 1];`
345			`return moves;`
346			`}`