如何按大小顺序输出链表数据？

Question

我被分配了一个任务，其中链接列表必须按大小打印国家名称及其人口。

链接列表和课程是由导师提供的，但是由于我们没有涵盖很多内容，因此我正在努力了解如何实际使用它！

到目前为止，我还没有读完这里和其他资料，所以我已经设法做到了这一点，不确定我是否诚实地在正确的轨道上。但是我完全不知道如何组织和打印链接列表！我不确定如何将节点定义为列出的项目。

class LinkedList:
    def __init__(self, data):
        self.label = data[0][0]
        self.value = data[0][1]
        self.tail = None if (len(data) == 1) else LinkedList(data[1:])

    def toString(self):
        countries = "{name}: {population}".format(name = self.label, population = self.value)
        if tail is not None:
            nextValue = set.tail.toString()
            countries = "{}, {}".format(countries, nextValue)
            return myValue

    def add_node(self, n): #Adding node function within the list.
        n.set_next(self.root)
        self.root = n
        self.size += 1

    def listSorting(self):
        if self.size > 1:
            newlist = []
            current = self.root
            newlist.append(self.root)
            while current.has_next():
                current = current.get_next()
                newlist.append(current)
            newlist = sorted(newlist, key = lambda node: node.get_data(), reverse = True);
            Linked = LinkedList()
            for node in newlist:
                Linked.add_node(node)
            return

    countries = LinkedList([("Ukraine",41879904),("Brunei",442400),("Christmas Island (Australia)",1928),("Mauritius",1265985),("Lesotho",2007201),("Guatemala",16604026),("British Virgin Islands (UK)",30030),("Malta",493559),("Greenland (Denmark)",56081),("Guernsey (UK)",62792),("Ethiopia",98665000),("Suriname",581372),("Turkmenistan",6031187),("American Samoa (US)",56700),("French Polynesia (France)",275918),("Equatorial Guinea",1358276),("Solomon Islands",680806),("Burundi",10953317),("Abkhazia",244832),("Rwanda",12374397),("Iceland",364260),("Monaco",38300),("Namibia",2458936),("United States",329532925),("Brazil",211402908),("Finland",5527573),("Armenia",2957500),("Wallis and Futuna (France)",11700),("Cuba",11209628),("Guyana",782766),("Oman",4664790),("Aruba (Netherlands)",112309),("Nauru",11000),("Sri Lanka",21803000),("Myanmar",54339766),("United Arab Emirates",9890400),("Hungary",9772756),("Norfolk Island (Australia)",1756),("Cambodia",15288489),("Fiji",884887),("Benin",11733059),("Egypt",100264508),("Northern Cyprus",351965),("Angola",31127674),("Barbados",287025),("Trinidad and Tobago",1363985),("Colombia",49395678),("Turks and Caicos Islands (UK)",41369),("Norway",5367580),("Kiribati",120100),("Kosovo",1795666),("Azerbaijan",10067108),("Romania",19405156),("Kyrgyzstan",6533500),("Peru",32131400),("Australia",25680766),("Faroe Islands (Denmark)",52124),("Turkey",83154997),("Georgia",3723464),("Singapore",5703600),("Eswatini",1093238),("Saint Vincent and the Grenadines",110608),("East Timor",1387149),("Tuvalu",10200),("Pakistan",219313520),("Bahrain",1543300),("Paraguay",7152703),("Jersey (UK)",106800),("Slovakia",5456362),("Mongolia",3313049),("Argentina",44938712),("Jordan",10660256),("Saint Barthélemy (France)",9793),("Andorra",77543),("Bangladesh",168456310),("Saint Martin (France)",35746),("FS Micronesia",104468),("South Sudan",12778250),("Artsakh",148000),("Slovenia",2094060),("Senegal",16209125),("Ivory Coast",25823071),("Syria",17500657),("Montserrat (UK)",4989),("Philippines",108505959),("Laos",7123205),("Gibraltar (UK)",33701),("Iran",83371987),("Bahamas",385340),("Mauritania",4077347),("Portugal",10276617),("Madagascar",26251309),("Malawi",19129952),("Central African Republic",5496011),("Saint Kitts and Nevis",52823),("Ghana",30280811),("Honduras",9158345),("Belarus",9408400),("India",1361140893),("Estonia",1328360),("Nicaragua",6460411),("Mali",20250833),("Zambia",17885422),("S\u00e3o Tom\u00e9 and Pr\u00edncipe",201784),("Cura\u00e7ao (Netherlands)",158665),("Jamaica",2726667),("Northern Mariana Islands (US)",56200),("Vanuatu",304500),("Kuwait",4420110),("Cameroon",26545864),("Netherlands",17456281),("Saudi Arabia",34218169),("Dominican Republic",10358320),("Japan",125950000),("Djibouti",1078373),("Antigua and Barbuda",96453),("Morocco",35871167),("Nigeria",206139587),("Iraq",39127900),("South Korea",51780579),("Pitcairn Islands (UK)",50),("US Virgin Islands (US)",104578),("Ireland",4921500),("Sierra Leone",7901454),("Cyprus",875900),("Palestine",4976684),("Luxembourg",626108),("Falkland Islands (UK)",3198),("France",67076000),("Bolivia",11469896),("Panama",4218808),("Seychelles",97625),("Guinea-Bissau",1604528),("Puerto Rico (US)",3193694),("Anguilla (UK)",14869),("Macau (China)",679600),("North Macedonia",2077132),("Saint Helena, Ascension",5633),("Sweden",10338368),("Kazakhstan",18683712),("China",1402247960),("Italy",60238522),("Israel",9186750),("Uzbekistan",34131625),("Guam (US)",172400),("Dominica",71808),("Malaysia",32752760),("New Zealand",4978784),("Cape Verde",550483),("Uruguay",3518552),("Belgium",11524454),("Kenya",47564296),("Saint Pierre and Miquelon (France)",6008),("Uganda",40299300),("Yemen",29825968),("Nepal",29996478),("Switzerland",8603899),("Sint Maarten (Netherlands)",40614),("Tonga",100651),("Algeria",43000000),("Haiti",11577779),("Zimbabwe",15159624),("North Korea",25450000),("Congo",5518092),("Belize",408487),("Czech Republic",10693939),("Poland",38379000),("San Marino",33574),("Tanzania",55890747),("Tokelau (NZ)",1400),("Saint Lucia",178696),("Cook Islands (NZ)",15200),("Mozambique",30066648),("Indonesia",266911900),("Grenada",112003),("Burkina Faso",20870060),("Western Sahara",582463),("New Caledonia (France)",282200),("Albania",2845955),("Greece",10724599),("Bosnia and Herzegovina",3301000),("Montenegro",622359),("Russia",146745098),("Samoa",200874),("Comoros",873724),("United Kingdom",66435550),("Taiwan",23604265),("Vatican City",799),("Austria",8902600),("Lebanon",6825442),("Latvia",1906800),("Mexico",126577691),("Venezuela",32219521),("Papua New Guinea",8935000),("Chad",16244513),("Canada",37996639),("Maldives",374775),("Denmark",5822763),("Tajikistan",9127000),("Isle of Man (UK)",83314),("Afghanistan",32225560),("Germany",83149300),("Vietnam",96208984),("Eritrea",3497117),("Spain",47100396),("Costa Rica",5058007),("Cayman Islands (UK)",65813),("Niger",22314743),("Liechtenstein",38749),("Gambia",2347706),("Hong Kong (China)",7500700),("Sudan",42432665),("Tunisia",11722038),("\u00c5land Islands (Finland)",29885),("DR Congo",89561404),("Bulgaria",6951482),("Liberia",4475353),("Botswana",2338851),("Palau",17900),("Niue (NZ)",1520),("Thailand",66494417),("South Africa",58775022),("Lithuania",2793471),("Gabon",2172579),("Libya",6871287),("Transnistria",469000),("Moldova",2681735),("South Ossetia",53532),("Guinea",12218357),("El Salvador",6486201),("Croatia",4076246),("Qatar",2747282),("Serbia",6963764),("Togo",7538000),("Ecuador",17466864),("Cocos (Keeling) Islands (Australia)",538),("Chile",19107216),("Bermuda (UK)",64027),("Somalia",15893219),("Bhutan",741672),("Marshall Islands",55500)])

print(countries)

Answer 1

尝试一下：

def print_list(self):
    root, nodes = self, []
    while root:
        nodes.append((root.label, root.value))
        root = root.tail
    nodes = sorted(nodes, key=lambda x: x[1])
    for node in nodes:
        print(f'{node[0]}: {node[1]}')

并调用此方法

countries.print_list()

Answer 2

LinkedList是一个递归构建对象。因此，让我们递归地检索其值：

def printll(ll):
    print(ll.label, ll.value)
    if ll.tail:
        printll(ll.tail)
    else:
        return


ll = LinkedList(data)
printll(ll)