double Probablistic_cell::getProbForOccupied(const bool reset)
{
if(log_odds == 0.0)
return -1;
double occupied_prob = 1 - 1 / (1 + std::exp(log_odds));
if(reset)
{
resetCell();
}
return occupied_prob;
}
int evaluateMaxMove( unsigned int *board, int depth )
{
int value, x, y;
int max = MIN_INFINITY-1;
int scores1[MAX_BOARD_SIZE][MAX_BOARD_SIZE];
int scores2[MAX_BOARD_SIZE][MAX_BOARD_SIZE];
// printf("DEPTH=%d\n", depth);
boards_checked++;
/*
for (i = 0; i < depth; i++) printf(" ");
printf("%d min %d %d\n", depth, last_move_x, last_move_y);
*/
/* Player 1 (min) just made a move, so we evaluate that move here */
if (checkPlayerWin(X_PLAYER, board)) return MIN_INFINITY;
/* If Player 2 has a winning position, take it */
for (x = 0; x < MAX_BOARD_SIZE; x++)
for (y = 0; y < MAX_BOARD_SIZE; y++) {
if (getCell(x, y, board) == EMPTY && hasNeighbor(x, y, board)) {
scores1[x][y] = countScore( O_PLAYER, x, y, board, 4);
if (scores1[x][y] == MAX_INFINITY) {
if (depth == 0) { computer_move_x = x; computer_move_y = y; }
return MAX_INFINITY;
}
}
}
/* If Player 1 has a winning position, block it */
for (x = 0; x < MAX_BOARD_SIZE; x++)
for (y = 0; y < MAX_BOARD_SIZE; y++)
if (getCell(x, y, board) == EMPTY && hasNeighbor(x, y, board)) {
scores2[x][y] = countScore( X_PLAYER, x, y, board, 4);
if (scores2[x][y] == MAX_INFINITY) {
putCell( O_PLAYER, x, y, board );
if (depth == 0) { computer_move_x = x; computer_move_y = y; return 0; }
max = evaluateMinMove( board, depth+1 );
resetCell( x, y, board);
return max;
}
}
/* Cutoff checking */
if (depth >= CUTOFF) {
// printf("depth %d scores\n", depth);
for (x = 0; x < MAX_BOARD_SIZE; x++)
for (y = 0; y < MAX_BOARD_SIZE; y++)
if (getCell(x, y, board) == EMPTY && hasNeighbor(x, y, board)) {
value = (scores2[x][y])+(scores1[x][y]<<1);
// printf("max (%d %d) %d %d %d\n", x, y, value, scores1[x][y], scores2[x][y]);
if (value > max) {
max = value;
}
}
return max;
}
for (x = 0; x < MAX_BOARD_SIZE; x++)
for (y = 0; y < MAX_BOARD_SIZE; y++)
if (getCell(x, y, board) == EMPTY && hasNeighbor(x, y, board)) {
putCell( O_PLAYER, x, y, board );
value = evaluateMinMove( board, depth+1 );
resetCell( x, y, board);
// printf("depth=%d value = %d for %d %d\n", depth, value, x, y);
if (value > max) {
max = value;
if (depth == 0) {
computer_move_x = x; computer_move_y = y;
}
if (max == MAX_INFINITY) return max;
}
}
/* No move is possible -- draw */
if (max == MIN_INFINITY-1) {
return DRAW;
}
return max;
}
int evaluateMinMove( unsigned int *board, int depth )
{
int value, x, y;
int min = MAX_INFINITY+1;
int scores1[MAX_BOARD_SIZE][MAX_BOARD_SIZE];
int scores2[MAX_BOARD_SIZE][MAX_BOARD_SIZE];
// printf("DEPTH=%d\n", depth);
boards_checked++;
/*
for (i = 0; i < depth; i++) printf(" ");
printf("%d max %d %d\n", depth, last_move_x, last_move_y);
*/
/* Player 2 (max) just made a move, so we evaluate that move here */
if (checkPlayerWin(O_PLAYER, board)) return MAX_INFINITY;
/* If Player 1 has a winning position, take it */
for (x = 0; x < MAX_BOARD_SIZE; x++)
for (y = 0; y < MAX_BOARD_SIZE; y++)
if (getCell(x, y, board) == EMPTY && hasNeighbor(x, y, board)) {
scores1[x][y] = countScore( X_PLAYER, x, y, board, 4);
if (scores1[x][y] == MAX_INFINITY) return MIN_INFINITY;
}
/* If Player 2 has a winning position, block it */
for (x = 0; x < MAX_BOARD_SIZE; x++)
for (y = 0; y < MAX_BOARD_SIZE; y++)
if (getCell(x, y, board) == EMPTY && hasNeighbor(x, y, board)) {
scores2[x][y] = countScore( O_PLAYER, x, y, board, 4);
if (scores2[x][y] == MAX_INFINITY) {
putCell( X_PLAYER, x, y, board );
min = evaluateMaxMove( board, depth+1 );
resetCell( x, y, board);
return min;
}
}
/* Cutoff checking */
if (depth >= CUTOFF) {
// printf("depth %d scores\n", depth);
for (x = 0; x < MAX_BOARD_SIZE; x++)
for (y = 0; y < MAX_BOARD_SIZE; y++)
if (getCell(x, y, board) == EMPTY && hasNeighbor(x, y, board)) {
// the value of position (x, y) is the sum of its score when the opponent is placed
// at that position plus the twice of the score when itself is placed at that position.
value = (scores2[x][y])+(scores1[x][y]<<1);
// printf("min (%d %d) %d %d %d\n", x, y, value, scores1[x][y], scores2[x][y]);
// the value is negated for min-move
value = -value;
if (value < min) {
min = value;
}
}
return min;
}
for (x = 0; x < MAX_BOARD_SIZE; x++)
for (y = 0; y < MAX_BOARD_SIZE; y++)
if (getCell(x, y, board) == EMPTY && hasNeighbor(x, y, board)) {
putCell( X_PLAYER, x, y, board );
value = evaluateMaxMove( board, depth+1 );
resetCell(x, y, board);
// printf("depth=%d value = %d for %d %d\n", depth, value, x, y);
if (value < min) {
min = value;
if (min == MIN_INFINITY) return min;
}
}
/* No move is possible -- draw */
if (min == MAX_INFINITY+1) {
return DRAW;
}
return min;
}
