public CheckerBoard(int size) {
        boardSize = size;
        checkersBoard = new char[boardSize][boardSize];
        typeR = 'r';
        typeB = 'b';
        empty = '_';
        typeRList = new LinkedList<Chip>();
        typeBList = new LinkedList<Chip>();
        for (int i = 0; i < boardSize; i++) {
            for (int j = 0; j < boardSize; j++) {
                if ((i + j) % 2 == 0) {
                    checkersBoard[i][j] = empty;    //EMPTY cell
                }
            }
        }
        for (int i = 0; i < (boardSize / 2) - 1; i++) {
            int j;
            if (i % 2 == 0) {
                j = 0;
            } else {
                j = 1;
            }
            while (j < boardSize) {
                checkersBoard[i][j] = typeR;    //RED piece
                typeRList.add(new Chip(j, i));
                j += 2;
            }
        }
        for (int i = boardSize - 1; i >= (boardSize) / 2 + 1; i--) {
            int j;
            if (i % 2 == 0) {
                j = 0;
            } else {
                j = 1;
            }
            while (j < boardSize) {
                checkersBoard[i][j] = typeB;     //BLACK piece
                typeBList.add(new Chip(j, i));
                j += 2;
            }
        }
    }