Python 3.x 中的二进制字符串搜索答案

【问题标题】：Binary string search in Python 3.xPython 3.x 中的二进制字符串搜索
【发布时间】：2013-11-22 15:47:07
【问题描述】：

我无法让这种二进制排序工作。我在lower_bound 和其他地方遇到语法错误。我知道这很明显，但我正处于办公桌的转折点。有人可以帮我让它清晰运行吗，我知道这是基本的东西，但我对此很陌生。

def main():
    sortNames()
    binarySearch()


def sortNames():
    global names
    names = ["Chris Rich", "Ava Fischer",  "Bob White", "Danielle Porter", "Gordon Pike", "Hannah Beauregard", "Matt Hoyle", "Ross Harrison", "Sasha Ricci", "Xavier Adams"]
    names.sort()


def binarySearch():
    global names, found, nameSearch, lower_bound, middle_pos, upper_bound
    nameSearch = string(input("What name are you looking for?")
    lower_bound = 0
    upper_bound = len(names)-1
    found = False
    while lower_bound <= upper_bound and not found:
        middle_pos = (lower_bound+upper_bound) // 2
        if name_list[middle_pos] < nameSearch:
            lower_bound = middle_pos + 1
        elif name_list[middle_pos] > nameSearch:
            upper_bound = middle_pos - 1
        else:
            found = True

    if found:
        print("The name is at position", middle_pos)
    else:
        print("The name was not in the list.")                               


main()

【问题讨论】：

标签： python sorting python-3.x binary-search

【解决方案1】：

您忘记在前面的行中添加最后一个右括号：

nameSearch = string(input("What name are you looking for?")
#               1--^  2--^                             2--^

另外，您没有定义函数string()。不是说需要，input() 返回一个字符串已经。

在那之后，我看到name_list 的错误，但大概您在此处发布的代码之外定义了该列表。

【讨论】：

该死的疼。但现在我让它工作了，我知道这很简单

【解决方案2】：

names = ["Chris Rich", "Ava Fischer",  "Bob White",\
         "Danielle Porter", "Gordon Pike", "Hannah Beauregard",\
         "Matt Hoyle", "Ross Harrison", "Sasha Ricci", "Xavier Adams"]

def sortNames():
    global names
    names.sort()

def binarySearch():
    global names, found, nameSearch, lower_bound, middle_pos, upper_bound

    nameSearch = raw_input("What name are you looking for?")
    lower_bound = 0
    upper_bound = len(names)-1
    found = False
    while lower_bound <= upper_bound and not found:
        middle_pos = (lower_bound+upper_bound) // 2
        if names[middle_pos] < nameSearch:
            lower_bound = middle_pos + 1
        elif names[middle_pos] > nameSearch:
            upper_bound = middle_pos - 1
        else:
            found = True
    if found:
        print("The name is at position", middle_pos)
    else:
        print("The name was not in the list.")                           

def main():
        sortNames()
        binarySearch()


if __name__ == "__main__":
    main()

输出

anukalp@anukalp-Latitude-E6400:~$ python del1.py
What name are you looking for?Ross Harrison
('The name is at position', 7)

【讨论】：