private void rotateLeft() {
        int[][] rotatedBoard = new int[BOARD_SIZE][BOARD_SIZE];
        
        for(int i=0;i<BOARD_SIZE;++i) {
            for(int j=0;j<BOARD_SIZE;++j) {
                rotatedBoard[BOARD_SIZE-j-1][i] = boardArray[i][j];
            }
        }
        
        boardArray=rotatedBoard;
    }