華爲筆試題
1．請你分別畫出OSI的七層網絡結構圖和TCP/IP的五層結構圖。
2．請你詳細地解釋一下IP協議的定義，在哪個層上面？主要有什麼作用？TCP與UDP呢？
3．請問交換機和路由器各自的實現原理是什麼？分別在哪個層次上面實現的？
4．請問C++的類和C裏面的struct有什麼區別？
5．請講一講析構函數和虛函數的用法和作用。
6．全局變量和局部變量有什麼區別？是怎麼實現的？操作系統和編譯器是怎麼知道的？
7．8086是多少位的系統？在數據總線上是怎麼實現的？
聯想筆試題
1．設計函數 int atoi(char *s)。
2．int i=(j=4,k=8,l=16,m=32); printf(“%d”, i); 輸出是多少？
3．解釋局部變量、全局變量和靜態變量的含義。
4．解釋堆和棧的區別。
5．論述含參數的宏與函數的優缺點
普天C++筆試題
1．實現雙向鏈表刪除一個節點P，在節點P後插入一個節點，寫出這兩個函數。
2．寫一個函數，將其中的/t都轉換成4個空格。
3．Windows程序的入口是哪裏？寫出Windows消息機制的流程。
4．如何定義和實現一個類的成員函數爲回調函數？
5．C++裏面是不是所有的動作都是main()引起的？如果不是，請舉例。
6．C++裏面如何聲明const void f(void)函數爲C程序中的庫函數？
7．下列哪兩個是等同的
int b;
A const int* a = &b;
B const* int a = &b;
C const int* const a = &b;
D int const* const a = &b;
8．內聯函數在編譯時是否做參數類型檢查？
void g(base & b){
b.play;
}
void main(){
son s;
g(s);
return;
}
1. How do you code an infinite loop in C?
2. Volatile:
（1）What does the keyword volatile mean? Give an example
（2）Can a parameter be both const and volatile? Give an example
（3）Can a pointer be volatile? Give an example
3. What are the values of a, b, and c after the following instructions:
int a=5, b=7, c;
c = a+++b;
4. What do the following declarations mean?
（1）const int a;
（2）int const a;
（3）const int *a;
（4）int * const a;
（5）int const * a const;
5. Which of the following statements describe the use of the keyword static?
（1）Within the body of a function: A static variable maintains its value between function revocations
（2）Within a module: A static variable is accessible by all functions within that module
（3）Within a module: A static function can only be called by other functions within that module
6. Embedded systems always require the user to manipulate bits in registers or variables. Given an integer variable a, write two code fragments.
The first should set bit 5 of a. The second shnuld clear bit 5 of a. In both cases, the remaining bits should be unmodified.
7. What does the following function return?
char foo(void)
{
unsigned int a = 6;
iht b = -20;
char c;
(a+b > 6) ? (c=1): (c=0);
return c;
}
8. What will be the output of the following C code?
main()
{
int k, num= 30;
k =(num > 5 ? (num <=10 ? 100:200): 500);
printf(“%d”, k);
}
9. What will the following C code do?
int *ptr;
ptr =(int *)Ox67a9;
*ptr = Oxaa55;
10. What will be the output of the follow C code?
#define product(x) (x*x)
main()
{
int i = 3, j, k;
j = product(i++);
k = product(++i);
printf(“%d %d”,j,k);
}
11. Simplify the following Boolean expression
!((i ==12) || (j > 15))
12. How many flip-flop circuits are needed to divide by 16?
13. Provides 3 properties that make an OS, a RTOS?
14. What is pre-emption?
15. Assume the BC register value is 8538H, and the DE register value is 62A5H.Find the value of register BC after the following assembly operations:
MOV A,C
SUB E
MOV C,A
MOV A,B
SBB D
MOV B,A
16. In the Assembly code shown below
LOOP: MVI C,78H
DCR C
JNZ LOOP
HLT
How many times is the DCR C Operation executed?
17. Describe the most efficient way (in term of execution time and code size) to divide a number by 4 in assembly language
18. what value is stored in m in the following assembly language code fragment if n=7?
LDAA #n
LABEL1: CMPA #5
BHI L3
BEQ L2
DECA
BRA L1
LABEL2: CLRA
LABEL3: STAA #m
19. What is the state of a process if a resource is not available?
#define a 365*24*60*60
20. Using the #define statement, how would you declare a manifest constant that returns the number of seconds in a year? Disregard leap years in your answer.
21. Interrupts are an important part of embedded systems. Consequently, many compiler vendors offer an extension to standard C to support interrupts. Typically, the keyword is __interrupt. The following routine (ISR). Point out problems in the code.
__interrupt double compute_area (double radius)
{
double area = PI * radius * radius;
printf(“/nArea = %f”, area);
return area;
}
維爾VERITAS軟件筆試題
1. A class B network on the internet has a subnet mask of 255.255.240.0, what is the maximum number of hosts per subnet .
a. 240 b. 255 c. 4094 d. 65534
2. What is the difference: between o(log n) and o(log n^2), where both logarithems have base 2 .
a. o(log n^2) is bigger b. o(log n) is bigger
c. no difference
3. For a class what would happen if we call a class’s constructor from with the same class’s constructor .
a. compilation error b. linking error
c. stack overflow d. none of the above
4. “new” in c++ is a: .
a. library function like malloc in c
b. key word c. operator
d. none of the above
5. Which of the following information is not contained in an inode .
a. file owner b. file size
c. file name d. disk address
6. What’s the number of comparisons in the worst case to merge two sorted lists containing n elements each .
a. 2n b.2n-1 c.2n+1 d.2n-2
7. Time complexity of n algorithm T(n), where n is the input size ,is T(n)=T(n-1)+1/n if n>1 otherwise 1 the order of this algorithm is .
a. log (n) b. n c. n^2 d. n^n
8. The number of 1’s in the binary representation of 3*4096+ 15*256+5*16+3 are .
a. 8 b. 9 c. 10 d. 12
揚智（科技）筆試題目
1. Queue is a useful structure
* What is a queue?
* Write 5 operations or functions, without details, that can be done on a queue.
2. Insert a sequence fo keys(24,49,13,20,59,23,90,35) into a data structure, which has no keys initially. Depict the data structure after these insertions, if it is:
* a heap tree
* an AVL tree
3. * What is a synchronous I/O bus?
* What is an asnchronous I/O bus?
* Compare the advantages and disadvantages of synchronous and a synchronous I/O bus.
4. Explain the following terminology:
* Baud rate
* Handshaking
* Memory mapped I/O
5. Explain the key issues in supporting a real-time operation system for embedded system.
6. Explain the mapping of visual addresses to real addresses under paging by
* direct mapping
* associative mapping
* combined direct/associated mapping
7. Please explain what is “write-back” and “write-through”, and discuss the advantage and disadvantage about these two methods.
8. Explain the concept and benefit of threads
9. What is hardware interrupt? What is software interrupt? What is exception? Please tell me all you know about interrupt.
10. Write a recursive function that tests wether a string is a palindrome. A palindrome is s string such as “abcba” or “otto” that reads the same in both directions.If you can write this function recursively,you can write an iterative version of this function instead.
11．什麼是進程（Process）和線程（Thread）？有何區別？
12．MFC和SDK有何區別？
13．IRP是什麼？有何作用？
14．Windows 2000操作系統下用戶模式和內核模式下編程有何區別？
15．驅動程序的BUFFER能swap到磁盤上去嗎？爲什麼？
16．試編寫3個函數實現
（1）建立一個雙向鏈表
（2）插入一個節點
（3）刪除一個節點
17．簡述Hardware interrupt和software中斷的區別，簡述其應用。
18．試編寫一個函數，計算一個字符串中A的個數。
19．畫出其相應流程圖並編寫一個函數實現一個整數到二進制數的轉換，如輸入6，輸出110。
20．
（1）編寫一個遞歸函數，刪除一個目錄。
（2）編寫一個非遞歸函數，刪除一個目錄。
並比較其性能。
廣東北電面試題目
英文筆試題
1. Tranlation (Mandatory)
CDMA venders have worked hard to give CDMA roaming capabilities via the development of RUIM-essentially, a SIM card for CDMA handsets currently being deployed in China for new CDMA operator China Unicom. Korean cellco KTF demonstrated earlier this year the ability to roam between GSM and CDMA using such cards.However,only the card containing the user’s service data can roam-not the CDMA handset or the user’s number (except via call forwarding).
2. Programming (Mandatory)
Linked list
a. Implement a linked list for integers,which supports the insertafter (insert a node after a specified node) and removeafter (remove the node after a specified node) methods;
b. Implement a method to sort the linked list to descending order.
3. Debugging (Mandatory)
a. For each of the following recursive methods,enter Y in the answer box if themethod terminaters (assume i=5), Otherwise enter N.
static int f(int i){
return f(i-1)*f(i-1);
}
Ansewr:
static int f(int i){
if(i==0){return 1;}
else {return f(i-1)*f(i-1);}
}
Ansewr:
static int f(int i){
if(i==0){return 1;}
else {return f(i-1)*f(i-2);}
}
Ansewr:
b. There are two errors in the following JAVA program:
static void g(int i){
if(i==1){return;}
if(i%2==0){g(i/2);return;}
else {g(3*i);return;}
}
please correct them to make sure we can get the printed-out result as below:
3 10 5 16 8 4 2 1
中文筆試題
1．漢譯英
北電網絡的開發者計劃使來自於不同組織的開發者，能夠在北電網絡的平臺上開發圓滿的補充業務。北電網絡符合工業標準的開放接口，爲補充業務的開展引入了無數商機，開發者計劃爲不同層面的開發者提供不同等級的資格，資格的劃分還考慮到以下因素：補充業務與北電網絡平臺的集合程度，開發者團體與北電網絡的合作關係，等等。
2．編程
將整數轉換成字符串：void itoa(int,char);
例如itoa(-123,s[])則s=“-123”;