CSOAHELP经常遇到来自各大科技公司的面试真题。今天,我们将分享几道来自Amazon的面试题,并提供详细的解题思路与点评。这些题目涉及字符串处理、数组操作以及文件系统操作,是非常典型的算法与数据结构问题。
题目一:寻找字符串中的第一个不重复字符
原题描述:
Q. Find first non-repeated character in a string.
Eg. AAABBBC, Returns C.
Eg. AAABBBCD, Returns C.
Eg. ABABABCD, Returns C.
解题思路: 这道题要求找到字符串中第一个不重复的字符。可以采用哈希表来记录每个字符的出现次数,遍历字符串,将每个字符的出现次数存储在哈希表中。然后再遍历一次字符串,找到第一个在哈希表中出现次数为1的字符。这种方法时间复杂度为O(n),其中n是字符串的长度,空间复杂度也是O(n),用于存储哈希表。
题目二:规范化文件路径
原题描述:
I’d like you to write a function. It will take a string as input. That string will be a file name (e.g. "/usr/bin").
That path might contain special directories "." (reference to self) and ".." (reference to parent directory).
Your function will return the name for the file without using special directories.
Example input/output
---------------------
Input: "/etc/tmp" -> [etc,tmp]
Output: "/etc/tmp"
Input: "/usr/bin/./some_file.sh" -> [usr,bin,.,some_file.sh]
Output: "/usr/bin/some_file.sh"
Input: "/usr/bin/../local"
Output: "/usr/local"
解题思路: 这个题目要求去除路径中的特殊符号"."和"..",并返回规范化后的路径。可以使用栈数据结构来处理路径分隔符。首先,将路径按照"/"分割,然后遍历每个部分:遇到"."时跳过,遇到".."时弹出栈顶元素(如果栈不为空),否则将当前部分压入栈中。最后将栈中的元素按"/"连接起来即可。
题目三:寻找数组中具有特定差值的所有配对
原题描述:
Write a function to accept two arguments. Arg1 being integer Array and Arg2 is an integer.
Find all the pairs from Arg1 which has diff equal to Arg2
eg.
Arg1 = [1,5,2,7,3]
Arg2 = 3
Output = True, (5,2)
Arg2 = 10
Output = False
解题思路: 此题要求在数组中找到差值等于指定值的所有配对。可以采用哈希表来记录每个数的位置。在遍历数组时,检查当前数加上目标差值或减去目标差值是否存在于哈希表中,如果存在,则说明找到了一个配对。该方法时间复杂度为O(n),空间复杂度也为O(n)。
题目四:模拟Unix的“find”命令
原题描述:
// Implement the functionality of the "find" command in UNIX as an API that returns a list of files based on
// the provided search parameters (Search should be limited to name and size only).
// For e.g.
// 1. Find all files that start with "abc"
// 2. Find all files that are greater than or equal 2Mb in size
// You can assume you are provided a File object which has the following methods:
// a. getName() - to get name of file or directory
// b. getSize() - to get the size of a file
// c. isDir() - is given path a directory or file
// d. listFiles() - returns a list of files if initialized with a directory
解题思路: 这个题目要求实现类似Unix中“find”命令的功能,基于文件名和大小进行搜索。可以通过递归遍历目录结构并应用搜索条件来实现。首先,检查当前路径是否是目录,如果是则递归处理其内容。然后,检查文件名和文件大小是否满足搜索条件,如果满足则将文件添加到结果列表中。这个方法需要结合文件系统的遍历与过滤操作,时间复杂度取决于文件系统的深度和文件数量。
总结
以上几道题目涉及了字符串处理、路径规范化、数组操作以及文件系统操作,都是Amazon面试中非常经典的题目。这些题目不仅考察了候选人的编程能力,还考察了他们解决问题的思路与方法。希望通过这些详细的解题思路与点评,能够帮助到正在准备面试的你。加油!
通过Amazon的面试不仅需要扎实的编程功底,还需要具备良好的沟通技巧和问题解决能力。希望这篇文章对你有所帮助。如果你觉得内容有价值,记得收藏我们的网站,以便获取更多面试技巧和技术文章。祝你面试顺利,成功斩获你的梦想工作!
With our powerful interview assistance, candidates can effectively analyze and communicate their solutions to these interview questions. This not only demonstrates their programming abilities to the interviewer but also showcases their clear problem-solving approach and effective communication skills. These abilities are valuable not only for Amazon interviews but also for solving real-world programming problems. We wish you all the best in your interviews!
If you need our interview assistance services, please contact us immediately.
面试辅助,面试代面,请联系我们。
![](https://csoahelp.com/wp-content/uploads/2024/05/image-39.png)