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1、Suppose that a selection sort of 80 items has completed 32 iterations of the main loop. How many items are now guaranteed to be in their final spot (never to be moved again)?
A、16 B、31 C、32 D、39 E、40
2、Which synchronization mechanism(s) is/are used to avoid race conditions among processes/threads in operating system?
A、Mutex B、Mailbox C、Semaphore D、Local procedure call
3、There is a sequence of n numbers 1,2,3,...,n and a stack which can keep m numbers at most. Push the n numbers into the stack following the sequence and pop out randomly . Suppose n is 2 and m is 3,the output sequence may be 1,2 or 2,1,so we get 2 different sequences . Suppose n is 7,and m is 5,please choose the output sequence of the stack.
A、1,2,3,4,5,6,7
B、7,6,5,4,3,2,1
C、5,6,4,3,7,2,1
D、1,7,6,5,4,3,2
E、3,2,1,7,5,6,4
4、Which is the result of binary number 01011001 after multiplying by 0111001 and adding 1101110?
A、0001010000111111
B、0101011101110011
C、0011010000110101
转化为10进制操作以后，再转化为二进制就可以了。
5、What is output if you compile and execute the following c code?
[cpp] view plaincopyprint?void main()
{
int i = 11;
int const *p = &i;
p++;
printf("%d",*p);
}
void main()
{
int i = 11;
int const *p = &i;
p++;
printf("%d",*p);
}A、11
B、12
C、Garbage value
D、Compile error
E、None of above
6、Which of following C++ code is correct ? C
A、
[cpp] view plaincopyprint?int f()
{
int *a = new int(3);
return *a;
}
int f()
{
int *a = new int(3);
return *a;
}B、[cpp] view plaincopyprint?int *f()
{
int a[3] = {1,2,3};
return a;
}
int *f()
{
int a[3] = {1,2,3};
return a;
}C、[cpp] view plaincopyprint?vector<int> f()
{
vector<int> v(3);
return v;
}
vector<int> f()
{
vector<int> v(3);
return v;
}D、[cpp] view plaincopyprint?void f(int *ret)
{
int a[3] = {1,2,3};
ret = a;
return ;
}
void f(int *ret)
{
int a[3] = {1,2,3};
ret = a;
return ;
}E、None of above
7、Given that the 180-degree rotated image of a 5-digit number is another 5-digit number and the difference between the numbers is 78633, what is the original 5-digit number？
A、60918 B、91086 C、18609 D、10968 E、86901
8、Which of the following statements are true
A、We can create a binary tree from given inorder and preorder traversal sequences.
B、We can create a binary tree from given preorder and postorder traversal sequences.
C、For an almost sorted array,Insertion sort can be more effective than Quciksort.
D、Suppose T(n) is the runtime of resolving a problem with n elements, T(n)=O(1) if n=1;
T(n)=2*T(n/2)+O(n) if n>1; so T(n) is O(nlgn)
E、None of above
9、Which of the following statements are true?
A、Insertion sort and bubble sort are not efficient for large data sets.
B、Qucik sort makes O(n^2) comparisons in the worst case.
C、There is an array :7,6,5,4,3,2,1. If using selection sort (ascending),the number of swap operations is 6
D、Heap sort uses two heap operations:insertion and root deletion （插入、堆调整）
E、None of above
10、Assume both x and y are integers,which one of the followings returns the minimum of the two integers?
A、y^((x^y) & -(x<y))
B、y^(x^y)
C、x^(x^y)
D、(x^y)^(y^x)
E、None of above