This exam in 7 pages, make sure to read all the questions and use the backside as a draft area. a. The old name of (C++) is (C version 2).

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1 This exam in 7 pages, make sure to read all the questions and use the backside as a draft area 1. (15 Points ) True or False? And correct the wrong statement? a. The old name of (C++) is (C version ). [ ] b. Object refers to an instance of a predefined Class in action (run time). [ ] c. If you didn't state the access specifiers of a Structure members. It will be public by default. [ ] d. In a -bit environment the size of a pointer to a Class object equals 4 bytes. [ ] e. With namespace you can divide global scope to sub-scopes, each one with its own name. [ ] f. Throw keyword can throw an Object. [ ] g. Try-catch statements are used to handle run-time errors in C++. [ ] h. If Aclass and Bclass are two distinct classes, then (Bclass *b=(aclass *)a) gives syntax error where a is an object of Aclass. [ ] i. If a class has a virtual method with implementation then this class is called abstract class. [ ] j. The term Overriding indicates the redefining of an existed method with different parameters. [ ] k. In OOP, polymorphism means, one thing with many distinct forms. [ ] l. In C++, the assignment operator (=) is overloaded by default. [ ] m. The template operator enables the program to define generic data type methods and classes. [ ] n. If your program has ( #define x ) you can change the value of x later in the program. [ ] o. fstream can open files in binary mode only. [ ] August 016 Page 1 of 7

2 . (10 points) Trace the following code then answer the questions: #include<stdio.h> class Number{ protected: int value; Number(){ printf("base class\n"); virtual print_it()=0; ; class Decimal: public Number{ public: Decimal(int v){ value=v; ; void print_it(){ printf("decimal:%d\n",value); class Hexdecimal: public Number{ public: Hexdecimal(int v){ value=v; void print_it(){ printf("hexdecimal:%x\n",value); ; int main() { Decimal d(15); d.print_it(); Hexdecimal h(15); h.print_it(); return 0; a. What is the expected output of line 6? b. What is the expected output of line 9? c. Remove lines 6,7, and 8. What is the expected output of line 5? d. Do you expect an error occurred if we removed line 9? Explain? e. What is the common name for the relation between print_it in class decimal and print_it in class Number? August 016 Page of 7

3 . (10 points) Trace the following code then answer the questions: 1 #include <iostream> 14 int main(){ using namespace std; 15 cin>>param::x>>param::y; 16 try{ 4 namespace param{ 17 cout<<div(); 5 float x, y; catch(int e){ 7 using namespace param; 0 cout<<"error:("<<e<<") divide by zero"; 8 float div(){ 1 9 int x=8; catch(char e){ 10 if(y==0) cout<<"error:("<<e<<") divide by zero"; 11 throw 1; 4 1 return x/y; 5 return 0; 1 6 f. What is the expected output if the user entered: 4 g. What is the expected output if the user entered: 4 0 h. Remove line 9; What is the expected output if the user entered: 4 i. Replace line 9 with: throw A ; What is the expected output if the user entered: 4 0 j. Is it possible to replace line 19-4 with one catch statement that can receive int and char errors at the same time? How? August 016 Page of 7

4 4. (9 points) Find distinct syntax errors in the following program and suggest an appropriate correction: #include <iostream> using namespace std; class Shape{ protected: int l,w; static int counter; public: Shape(){ counter++; void set_values(int l, int w){ this->l=l; this->w=w; void show_data(){ cout<<counter<<endl; cout<<l<<endl; cout<<w<<endl; float area()=0; ; int counter=0; class Rect: Shape{ ; float area (){ return (l*w); class Tri: public Shape{ float area (){ return (0.5*l*w); ; int main (){ Shape *s1=new Rect(); s1->set_values(,); cout<<s1->area()<<endl; Shape *s=new Tri(); s->set_values(,); s->show_data(); return 0; NO. Line Reason correction August 016 Page 4 of 7

5 5. (6 points) Write C++ class Fman with two methods copy(char *source, char *dist) and remove(char *source) to handle binary files using fstream classes. August 016 Page 5 of 7

6 6. (10 points) Define a Money class, suitable for storing money information. The Class contains two int fields: pound and piaster. Write appropriate constructor to allow the user to set its data. Also write a print methods that prints out an object's info. Overload the + operator, so that adding two objects of this class works. As an added requirement, after adding two Money objects, values of more than 100 piaster should be converted to pounds. As an example: Money m1(,99), m(0,1); Money m=m1+m; m.print(); //should produce the following output: pounds August 016 Page 6 of 7

7 Note: continue your answer for question 6 here if needed August 016 Page 7 of 7 Do your best, Good Luck