Question

我有这段代码

def readCountries(self):
    countryList = []
    with open('countries.txt', 'r') as countryText:
        for line in open('countries.txt', 'r'):
            countries = countryText.read()
            countryList.append(line.strip().split())
        return countryList

此代码输出countries.txt，如下所示：

[[ “阿富汗”，647500.0,25500100]，[ “阿尔巴尼亚”，28748.0,2821977]，...，[ “津巴布韦”，390580.0,12973808]]

经过[name, area, population]。我要做的是编写一个函数，从上面的代码中调用答案来获取国家/地区列表并进行二进制搜索并打印国家/地区信息（如果找到）。示例：

printCountry("Canada")

  Canada, Area: 9976140.0,  Population: 35295770

 printCountry("Winterfell")

  I'm sorry, could not find Winterfell in the country list.

我不知道如何做这部分，感谢任何帮助。

Answer 1

希望这会有所帮助：

def binary_search(clist, cname):
    low = 0
    high = len(clist)
    while low<=high: 
        mid = int((low+high)/2)
        print(mid, low, high)
        if clist[mid][0]== cname:
            return clist[mid]
        elif clist[mid][0] > cname:
            high = mid-1
        else:
            low = mid+1

def printCountry(self,country_name):
    country = binary_search(self.countryList, country_name)
    if country:
        print("{0}, Area:{1}, Population:{2}".format(country[0],    country[1], country[2]))
    else:
        print("I'm sorry, could not find {0} in the country list.".format(country_name))

二进制搜索列表

1 个答案: