midterm1 S17

SJSU CMPE 126 S17 –Midterm 1 Exam

Assume there is a stock class which has symbol (string), cost (int) and shares (int) as public members.

• 1. Write the minimum declaration that supports both statements

stock s2(“APPL”, 209, 77), s3(“FB”, 100, 1); // 77 shares of APPL at $209, 1 share of FB at $100

stock s4(s3);

• 1. Write member operator overload function declaration that supports

  2. int value=s2+s3; // value is the sum of (cost*shares)

  3. Given the stock class has the following declaration:

friend ostream& operator>> (istream&, stock&);

Answer each of the following questions in less than 10 words.

• 1. Can this function be implemented as a “member function”? If yes, how? If no, why?

  2. Can this function be implemented without the “friend” declaration? If yes, how? If no, why?

  3. If we create a stockDB class which stores variable number of stocks in a dynamic stock array. Complete the minimum stockDB.h class definition such that

stockDB frank(5), obama(700); // frank can have at most 5 stocks, obama 700 max

class stockDB {

• 1. (3pt) Write the implementation code (cpp) that supports frank = obama;

  2. (3pt) Further assume that stock has operator< overloaded and there is a global swap(stock&, stock&) function. Complete the following implementation code for stockDB selection sort.

void stockDB::selectionSort() {

• 1. Add additional code below to cause a dangling pointer issue.

int * a = new int(5);

int * b = a;

• 1. Given the declaration int * d = new int[5]; Check ALL statements that prints out the address of the 2nd elements in d array

     1. cout << d + 1;

     2. cout << d + 4;

     3. cout << &d[1];

     4. cout << &d+4;

     5. cout << d++; // this is a bit tricky

  2. Is the following code correct? If yes, what’s the output? If no, what’s wrong?

int *p; //Line 1

int *q; //Line 2

p = new int; //Line 3

*p = 43; //Line 4

q = p; //Line 5

*q = 52; //Line 6

delete q; //Line 7

cout << *p << " " << *q << endl; //Line 8