微软2014校园招聘笔试试题及答案分析

Which of the following is(are) true about providing security to database servers ? Select all that apply.

• A、Do not host a database server on the same server as your web server
• B、Do not host a database server on a server based system
• C、Do not use blank password for SA account
• D、Employ a centralized administration model

题目分析：此题为数据库安全题目

A table CANNOT have one or more of the following index configurations.

• A、No indexes
• B、A clustered index
• C、clustered index and many non-clustered indexes
• D、Many clustered index

题目分析：聚集索引。索引是通过二叉树的数据结构来描述的，我们可以这么理解聚簇索引：索引的叶节点就是数据节点。而非聚簇索引的叶节点仍然是索引节点，只不过有一个指针指向对应的数据块，故聚集索引规定数据在表中的物理存储顺序，因此一个表只能包含一个聚集索引。但该索引可以包含多个列（组合索引），就像电话簿按姓氏和名字进行组织一样。

而非聚集索引一个表可以存在多个。

聚集索引存储记录是物理上连续存在，而非聚集索引是逻辑上的连续，物理存储并不连续。

• • Which of the following can be referred to as attack method(s)? Select all that apply.

    • A、Vulnerability scan
    • B、SQL Injection
    • C、Drive-by downloading
    • D、Brute force
      
      

题目分析：黑客

To speed up data access , we build cache system. In one system , The L1 cache access time is 5 ns , the L2 cache access time is 50 ns and the memory access time is 400 ns. The L1 cache miss rate is 50% , the L2 cache miss rate is 10%. The average data access time of this system is:

• A、5
• B、30
• C、45
• D、50
• E、55
• 
  

题目分析：

 In which case(s) would you use an outer join?

• A、The table being joined have NOT NULL columns.
• B、The table being joined have only matched data.
• C、The columns being joined have NULL values.
• D、The table being joined have only unmatched data.
• E、The table being joined have both matched and unmatched data.

题目分析：外连接（数据库）。outer join则会返回每个满足第一个（顶端）输入与第二个（底端）输入的联接的行。它还返回任何在第二个输入中没有匹配行的第一个输入中的行。外连接分为三种：左外连接，右外连接，全外连接。

• •  When a dll is loaded into memory, which part(s) can be shared between processes?

• • A、code segment
  • B、static variable
  • C、global variable
  • D、external difinitions and references for linking
  • E、BSS segment
• 
  

• • 题目分析：

    In the image below , if the function is designed to multiply two positive numbers which line number in the image contains the biggest functional bug(assume no overflow)?

    
    

• • A、Line 1
  • B、Line 2
  • C、Line 3
  • D、Line 4
  • E、Line 5
  
  

• 题目分析：应为 C+=A，B个A相加。
  
  • 
    

    
    

     Which statement(s) is(are) correct about thread and process？Select all that apply.

    
    

    
    

    
    

• • 
    
    
    
    A、Threads share the same address space of the parent process;Processes share the same address space of the parent process.
  • B、Changes to the main thread(cancellation，priority change，etc.) may affect the behavior of the other threads of the process; Changes to the parent process does not affect child processes.
  • C、Multiple threads mar cause deadlock,while multiple processes won't cause deadlock.
  • D、Threads can directly communicate with other threads of its process; Processes must use inter-process communication to communicate with sibling processes.
  • E、None of the above.
  • 
    
• • 
    

题目解析：进程是程序的一次执行。线程可以理解为进程中的执行的一段程序片段。两者间的差别： 进程间是独立的，这表现在内存空间，上下文环境；线程运行在进程空间内。 一般来讲（不使用特殊技术）进程是无法突破进程边界存取其他进程内的存储空间；而线程由于处于进程空间内，所以同一进程所产生的线程共享同一内存空间。 同一进程中的两段代码不能够同时执行，除非引入线程。 线程是属于进程的，当进程退出时该进程所产生的线程都会被强制退出并清除。 线程占用的资源要少于进程所占用的资源。 进程和线程都可以有优先级。 在线程系统中进程也是一个线程。可以将进程理解为一个程序的第一个线程。

• •  Which regular expression(s) matches the sentence "www.microsoft.com" ?

    • 
      
      
      
      
      
      
      
      A、^\w+\.\w+\.\w+$
    • B、[w]{0,3}.[a-z]*.[a-z]+
    • C、.[c-w.]{3,10}[.][c-w.][.][a]|.+
    • D、[w][w][w][microsoft]+[com]+
    • E、\w*
    
    

    
    

  
  

• • 题目分析：正则表达式，语法参考 http://www.cnblogs.com/lin714115/archive/2010/09/25/1834690.html
  • 
    

     Which of the following method(s) could be used to optimize the speed of a program ?

• • A、Improve memory access pattern to decrease cache misses.
  • B、Use special instructions(e.g. vector instructions) to replace compiler generated assembly code.
  • C、Change an algorithm from recursive implementation to iterative implementation.
  • D、Loop unwinding.
  
  

• • 
    

     Which is(are) valid function pointer declaration(s) below ? Select all that apply.

• • A、void* f(int);
  • B、int (*f)();
  • C、void (*f(int , void(*)(int)))(int);
  • D、void (*(*f)(int))();
  
  

• • 题目分析：函数指针http://blog.csdn.net/mei0720/article/details/39184837
    

     Which of the following method(s) CANNOT be used for Text-encryption:

• • A、MD5
  • B、RSA
  • C、RC4
  • D、DES
  
  

• • 
    

     The best time complexity of quick sort algorithm is:

• • A、O(lgn)
  • B、O(n)
  • C、O(nlgn)
  • D、O(n*n)
  
  

• • 
    

    As shown in the graph , start from node B , traverse the nodes on a Depth-First Search(DFS) algorithm , which is(are) the possible traversa sequence(s)? Select all that apply.

    
    

• • A、BADECF
  • B、BADEFC
  • C、BCAFDE
  • D、BCFDEA
  • E、BFDECA
  
  

• • 
    
  • • 
      

     Let's assume one type of cancer may be mis-diagnosed in the examination. 5 out of 100 people with this cancer will be diagnosed as not having it , and 1 out of 100 people without this cancer will be diagnosed as having it. We know the chance of getting this cancer is around 0.1%. One person was examined and diagnosed of having this cancer, which of the following value if the closest to the chance of is really having it?

• • A、90%
  • B、50%
  • C、30%
  • D、10%
  
  

• • 
    

    Asume you have an object to describe customer data:

       {

         ID（7 digit numeric）

         Family Name（string）

         Account Balance（currency）

       }

    If you have 500,000 Chinese customers records represented by instances of this object type , what set of data structures is best to get fast retrieval of customers (1) get IDs from Name and (2) get Name from ID?

• • A、(1) Tree with Hash(100 bucket) at leaves(2) Tree with linked list at leaves.
  • B、(1) Tree with linked list at leaves(2) Array.
  • C、(1) Tree with linked list at leaves(2) Hash(10,000 buckets)
  • D、(1) Sort linked list(2) Array.
  
  

• • 
    

     How many times is f() called when calculating f(10)?

         int f(int x)  

           {

               if(x <= 2)  

                   return 1;  

               return f(x – 2) + f(x – 4) +1;  

           }

• • A、14
  • B、18
  • C、20
  • D、24
  • E、None of the above.
  
  

• • 
    

     Which of the follwing sequence(s) could not be a postorder tree walk result of a binary search tree?

• • A、1,2,3,4,5
  • B、3,5,1,4,2
  • C、1,2,5,4,3
  • D、5,4,3,2,1
  
  

• • 
    

     Initialize integer i as 0, what's the value of i after the following operation?

       i += i > 0 ? i++ : i –;

• • A、-2
  • B、-1
  • C、0
  • D、1
  • E、2

• • 
    
    http://blog.csdn.net/mei0720/article/details/39184837：

     Which statement(s) below regarding TCP(Transmission Control Protocol) is(are) correct? Select all that apply.

• • A、TCP provides a way for applications to send encapsulated IP datagrams and send them without having to establish a connection.
  • B、TCP supports multicasting.
  • C、Port numbers below 1024 are called well-known ports and are reserved for standard services. For example,port 21 is reserved for FTP protocol, and port 25 is for SMTP protocol.
  • D、TCP handles package loss reliably.
  • E、None of the above.