Content of ReversiBoard.java extracted from reversi.jar
/* class ReversiBoard implements the board of the game Reversi used by Reversi.java 10-12-2006 version 0.1: initial release 16-12-2017 version 0.2: refactored */ import java.util.Random; public class ReversiBoard implements Strategy { TKind[][] board = new TKind[8][8]; int[] counter = new int[2]; // 0 = black, 1 = white boolean PassCounter; public ReversiBoard() { clear(); } public TKind get(int i, int j) { return board[i][j]; } public void set(Move move, TKind player) { switch (board[move.i][move.j]) { case white: counter[1]--; break; case black: counter[0]--; break; } board[move.i][move.j] = player; switch (player) { case white: counter[1]++; break; case black: counter[0]++; break; } } public int getCounter(TKind player) { return counter[player.ordinal() - 1]; } public void clear() { for (int i = 0; i < 8; i++) for (int j = 0; j < 8; j++) board[i][j] = TKind.nil; board[3][4] = TKind.black; board[4][3] = TKind.black; board[3][3] = TKind.white; board[4][4] = TKind.white; counter[0] = 2; counter[1] = 2; PassCounter = false; } public void println() { System.out.print("["); for (int i = 0; i < 8; i++) { for (int j = 0; j < 8; j++) System.out.print(board[i][j] + ","); System.out.println((i == 7 ? "]" : "")); } } public int move(Move move, TKind kind) { return checkBoard(move, kind); } public boolean gameEnd() { return counter[0] + counter[1] == 64; } private int Check(Move move, int incx, int incy, TKind kind, boolean set) { TKind opponent; int x = move.i; int y = move.j; if (kind == TKind.black) opponent = TKind.white; else opponent = TKind.black; int n_inc = 0; x += incx; y += incy; while ((x < 8) && (x >= 0) && (y < 8) && (y >= 0) && (board[x][y] == opponent)) { x += incx; y += incy; n_inc++; } if ((n_inc != 0) && (x < 8) && (x >= 0) && (y < 8) && (y >= 0) && (board[x][y] == kind)) { if (set) for (int j = 1; j <= n_inc; j++) { x -= incx; y -= incy; set(new Move(x, y), kind); } return n_inc; } else return 0; } private int checkBoard(Move move, TKind kind) { // check increasing x int j = Check(move, 1, 0, kind, true); // check decreasing x j += Check(move, -1, 0, kind, true); // check increasing y j += Check(move, 0, 1, kind, true); // check decreasing y j += Check(move, 0, -1, kind, true); // check diagonals j += Check(move, 1, 1, kind, true); j += Check(move, -1, 1, kind, true); j += Check(move, 1, -1, kind, true); j += Check(move, -1, -1, kind, true); if (j != 0) set(move, kind); return j; } private boolean isValid(Move move, TKind kind) { // check increasing x if (Check(move, 1, 0, kind, false) != 0) return true; // check decreasing x if (Check(move, -1, 0, kind, false) != 0) return true; // check increasing y if (Check(move, 0, 1, kind, false) != 0) return true; // check decreasing y if (Check(move, 0, -1, kind, false) != 0) return true; // check diagonals if (Check(move, 1, 1, kind, false) != 0) return true; if (Check(move, -1, 1, kind, false) != 0) return true; if (Check(move, 1, -1, kind, false) != 0) return true; if (Check(move, -1, -1, kind, false) != 0) return true; return false; } private class resultFindMax { int max, nb, nw; }; private resultFindMax findMax(int level, TKind me, TKind opponent, Strategy mStrategy) { int min, score, tnb, tnw; TKind[][] TempBoard = new TKind[8][8]; int[] TempCounter = new int[2]; resultFindMax res = new resultFindMax(); level--; res.nb = counter[0]; res.nw = counter[1]; for (int i = 0; i < 8; i++) System.arraycopy(board[i], 0, TempBoard[i], 0, 8); System.arraycopy(counter, 0, TempCounter, 0, 2); min = 10000; // high value for (int i = 0; i < 8; i++) for (int j = 0; j < 8; j++) if ((board[i][j] == TKind.nil) && (checkBoard(new Move(i, j), me) != 0)) { if (level != 0) { resultFindMax tres = findMax(level, opponent, me, mStrategy); tnb = tres.nb; tnw = tres.nw; score = tres.max; } else { tnb = counter[0]; tnw = counter[1]; score = counter[opponent.ordinal() - 1] - counter[me.ordinal() - 1] + mStrategy.strategy(me, opponent, board); } if (min > score) { min = score; res.nb = tnb; res.nw = tnw; } for (int k = 0; k < 8; k++) System.arraycopy(TempBoard[k], 0, board[k], 0, 8); System.arraycopy(TempCounter, 0, counter, 0, 2); } res.max = -min; return res; } public boolean findMove(TKind player, int llevel, Move move, Strategy mStrategy) { TKind[][] TempBoard = new TKind[8][8]; int[] TempCounter = new int[2]; int nb, nw, min, n_min; boolean found; resultFindMax res = new resultFindMax(); Random random = new Random(); if (counter[0] + counter[1] >= 52 + llevel) { llevel = counter[0] + counter[1] - 52; if (llevel > 5) llevel = 5; } for (int i = 0; i < 8; i++) System.arraycopy(board[i], 0, TempBoard[i], 0, 8); System.arraycopy(counter, 0, TempCounter, 0, 2); found = false; min = 10000; // high value n_min = 1; for (int i = 0; i < 8; i++) for (int j = 0; j < 8; j++) if ((board[i][j] == TKind.nil) && (checkBoard(new Move(i, j), player) != 0)) { if (player == TKind.black) res = findMax(llevel - 1, TKind.white, player, mStrategy); else res = findMax(llevel - 1, TKind.black, player, mStrategy); if ((!found) || (min > res.max)) { min = res.max; nw = res.nw; nb = res.nb; move.i = i; move.j = j; found = true; } else if (min == res.max) { // RANDOM MOVE GENERATOR n_min++; if (random.nextInt(n_min) == 0) { nw = res.nw; nb = res.nb; move.i = i; move.j = j; } } // if found // then PreView(nw,nb); for (int k = 0; k < 8; k++) System.arraycopy(TempBoard[k], 0, board[k], 0, 8); System.arraycopy(TempCounter, 0, counter, 0, 2); } return found; } public boolean userCanMove(TKind player) { for (int i = 0; i < 8; i++) for (int j = 0; j < 8; j++) if ((board[i][j] == TKind.nil) && isValid(new Move(i, j), player)) return true; return false; } /* normal strategy public int strategy(TKind me, TKind opponent, TKind[][] board) { int tstrat = 0; for (int i = 0; i < 8; i++) if (board[i][0] == opponent) tstrat++; else if (board[i][0] == me) tstrat--; for (int i = 0; i < 8; i++) if (board[i][7] == opponent) tstrat++; else if (board[i][7] == me) tstrat--; for (int i = 0; i < 8; i++) if (board[0][i] == opponent) tstrat++; else if (board[0][i] == me) tstrat--; for (int i = 0; i < 8; i++) if (board[7][i] == opponent) tstrat++; else if (board[7][i] == me) tstrat--; return tstrat; } */ public int strategy(TKind me, TKind opponent, TKind[][] board) { int tstrat = 0; for (int i = 0; i < 8; i++) if (board[i][0] == opponent) tstrat++; else if (board[i][0] == me) tstrat--; for (int i = 0; i < 8; i++) if (board[i][7] == opponent) tstrat++; else if (board[i][7] == me) tstrat--; for (int i = 0; i < 8; i++) if (board[0][i] == opponent) tstrat++; else if (board[0][i] == me) tstrat--; for (int i = 0; i < 8; i++) if (board[7][i] == opponent) tstrat++; else if (board[7][i] == me) tstrat--; if (board[0][0] == opponent) tstrat += 4; else if (board[0][0] == me) tstrat -= 4; if (board[0][7] == opponent) tstrat += 4; else if (board[0][7] == me) tstrat -= 4; if (board[7][0] == opponent) tstrat += 4; else if (board[7][0] == me) tstrat -= 4; if (board[7][7] == opponent) tstrat += 4; else if (board[7][7] == me) tstrat -= 4; return tstrat; } }
