Tencent QQ PHP programmer interview questions compilation_PHP tutorial

Said before:
1. The following questions, except for programming tasks, 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.
2. Time:
Basic tasks + advanced tasks + design tasks = 90 minutes
Programming tasks = 60 minutes

Basic tasks:
1. Please list the UNIX signals you can think of and explain their uses.
2. Please list all the string search algorithms you can think of and briefly explain them with comments.
3. There is an IP address (192.168.0.1), please write its 32-bit unsigned integer form.
４. 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 - selection (will get extra points):
1. Draw a few server-side models you are most familiar with (the format is not important, just try to make the drawings clear and explain the ideas)

Advanced tasks:
1. PHP garbage collection What is the mechanism?
Instructions:
1) If you are familiar with PHP source code, then please start from the source code and answer some questions, you will get extra points
2) If you are not familiar with PHP source code, then do your best , you can write more, including information obtained by using your own programming intuition.
３) If you are correct, you will get points. If you are wrong, you will not be deducted. If you do not write, you will get no points.
2. Please write the HTTP header and meet the following requirements:
1) This is a post request
2) Target: http://www.example.com:8080/test
3 )POST variable:
　username: test
　pwd: test2
　intro: Hello world!
　４）Contains the following COOKIE information:
　cur_query: you&me
　Description:
　1) If you can't remember the command words in a certain HTTP protocol, then you have no choice but to use "Chinese characters" instead.
2) If you can remember more HTTP protocol command words, then there is always no harm in writing a few more sentences, right?
３) The most important thing is to draw the correct "outline" (remember the header printed by tools such as httpwatch? That is the meaning of "outline"), there will also be points, but if, even " "Outline" is written wrong, so it's a pity.

Design tasks:
1. Recently, there are always people harassing our voting module, and we need you to design something with voting restrictions
The requirements are as follows:
1) Require each QQ number ( Assuming that this QQ number can be expressed in UNIT32) only 5 votes can be cast in 10 minutes.
　2) Our users are very enthusiastic, with an average of about 20 million people voting through this program every day.
Instructions:
1) No need to write code, just pictures and text.
2) For the key logic, please use pictures and code to express it. This is also a test of your writing ability.
　3) List all the boundary conditions you can think of. This is a test of your comprehensiveness and agility in logical thinking.
　4) For storage, do your best. 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:
1. We ran into trouble. A new missionary annoyed God. God was very angry and asked us to memorize the Bible (bbe.txt) until he said which word, we have to quickly answer which line and word position the word is in. I heard that you are an excellent programmer, so please help us complete this impossible task.
　The requirements are as follows:
　1)/myworks/example/bbe.txt, a 98 version English Bible
　2) The input part requirements are as follows: php ./example.php [word]
　３) 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 2...
Explanation:
1) This The text is 4MB huge...
2) The meaning of the word: a string composed of English letters (upper and lower case) and numbers (0-9)
3) The OS of the machine provided to you is ubuntu 9.10, and the memory is only 1G, and, unfortunately, 700M of it was used for other things
４) 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. CHM on the desktop of the computer In the folder, there is the corresponding PHP reference manual
5) The algorithm complexity requirement cannot be greater than O(N^2) (that is, the square of N)
6) 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