Tencent PHP programmer interview questions sharing

This article shares an interview question that is said to be a PHP programmer interview question from Tencent. It is not like the usual interview questions. Friends in need can come in and take a look. Topic recommendation: PHP interview questions and answers

Except for programming tasks, the following questions need to be written on the scratch paper provided to you. Paper is a precious earth resource, please use it sparingly. When there is a corresponding environment, programming tasks will require writing on the computer. If there are no conditions, you can only write on straw paper. Time: basic tasks + advanced tasks + design tasks = 90 minutes, programming tasks = 60 minutes.

Basic tasks: Please list the UNIX signals you can think of and explain their uses. Please list all the string search algorithms you can think of and briefly explain them with comments. There is an IP address (192.168.0.1), please write its 32-bit unsigned integer form. Write down all the HTTP return status values ​​you can think of and explain their uses (for example: returning 404 means page not found)

Basic task-choice (will get extra points):

Draw a few server-side models that you are most familiar with (the format is not important, just try to make the drawings clear and explain the ideas)

Advanced tasks: What is PHP's garbage collection mechanism? If you are familiar with PHP source code, then please start from the source code and answer some questions, you will get extra points. If you are not familiar with PHP source code, then try your best to write more, including information obtained by using your own programming intuition. If you are correct, you will get points. If you make mistakes, you will not be deducted. If you do not write down, you will get no points. Please write the HTTP header and meet the following requirements: This is a post request Target: http://bbs.it-home.org:8080/test POST variables: username: test, pwd: test2, intro: Hello world! Contains the following COOKIE information: cur_query: you&me

Instructions: If you can't remember the command words in a certain HTTP protocol, then the last resort is to use "Chinese characters" instead. If you can remember more HTTP protocol command words, then there is always no harm in writing a few more sentences, right? The most important thing is that you only need to draw the correct "outline" (remember the header printed by tools such as httpwatch? That is the meaning of "outline"), and there will be points, but if you even write the "outline" wrong , then it would be a pity.

Design tasks: Recently, there are always people harassing our voting module, and we need you to design something with voting restrictions. The requirements are as follows:

It is required that each QQ number (assuming this QQ number can be expressed in UNIT32) can only cast 5 votes within 10 minutes. Our users are very active, with an average of about 20 million people voting through this program every day.

Instructions: No need to write code, just pictures and text. For the key logic, please use pictures and codes to express it. This is also a test of your written expression ability. List all the boundary conditions you can think of. This is a test of your comprehensiveness and agility in logical thinking. For the storage part, do what you can. If you need a storage layer designed by yourself, then describe the implementation of this storage layer clearly in words and pictures. If the design is reasonable, you will get gorgeous bonus points.

Programming tasks: A new missionary annoyed God. God was very angry and asked us to memorize the Bible (bbe.txt). When he said a word, we had to quickly answer which line and word position the word was in. . I heard that you are an excellent programmer, so help us complete this impossible task.

The requirements are as follows: /myworks/example/bbe.txt, a 98 version English Bible The input part requirements are as follows: php ./example.php [word] The output part is as follows: [Word] 1,2 2,4 5,6 means: this word is in row 1 and column 2 (the second word), row 2 and column 4...

Instructions: This text is 4MB huge... The meaning of the word: a string composed of English letters (upper and lower case) and numbers (0-9) The OS of the machine provided to you is Ubuntu 9.10, and the memory is only 1G. And, unfortunately, 700M of it is used for other purposes. The computer-based exam does not allow access to the Internet, but I installed the man document and a reader for reading CHM and PDF. There is a corresponding PHP reference manual in the CHM folder on the desktop of my computer. The algorithm complexity requirement cannot be greater than O(N^2) (that is, the square of N) What? PHP is inefficient and uncomfortable to use. Well, you can do it in other languages. But note: the machine provided to you only has python 2.4/perl 5.8/gcc[g++] 4.1.

After reading the above PHP interview questions, what do you think? If you can understand and master everything, have you entered the ranks of experts and can directly join Tencent?