$25
1. What is encapsulation in OOP? Give an example
2. (2 pts) What is the time complexity of fun(). Please show your proof.
int fun(int n)
{
int count = 0;
for (int i = n; i > 0; i /= 2) for (int j = 0; j < i; j++) count += 1; return count;
}
3. Give a concise formula that gives the approximate number of digits in a positive integer. The integer is written in base 10.
4. What are the differences between references and pointers?
5. What are the three ways we can use items defined in a namespace. Include examples in your answer.
6. (2 pts) Discuss about the output of the following code. How the result will change if we replace struct with class?
1. struct Test {
2. int x;
3. }; 4.
5. int main() {
6. Test t;
7. t.x = 20;
8. cout<t.x<endl;
9. return 0;
10. }
7. (2 pts) A The header of the point class is as follows:
1. class point
2. {
3. public:
4. // CONSTRUCTOR
5. point (double initial_x = 0.0, double initial_y = 0.0); 6.
7. // MODIFICATION MEMBER FUNCTIONS
8. void set_x (double& value);
9. void set_y (double& value);
10.
11. // CONST MEMBER FUNCTIONS
12. point operator+ (double& in) const;
13.
14. private:
15. double x; // x coordinate of this point
16. double y; // y coordinate of this point
17.
18. };
§ Which line of the following code results in an error? Explain why. § What’s the solution?
8. (2 pts) What is the output of this code? Discuss your answer.