Al Imam Mohammad Ibn Saud Islamic University College of Computer and Information Sciences Computer Science Department

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1 Al Imam Mohammad Ibn Saud Islamic University College of Computer and Information Sciences Computer Science Department Privileges: Course Title: Computer Programming 1 Course Code: CS140 Course Instructors: Dr Laith Alsulaiman, Dr Mubarak Albathan, Dr Mohamed-Foued Sriti, Dr Saad Alabbad, Dr Zakir Ahmed Exam: Midterm Exam 1 Semester: Spring 2016 Date: TUE 22/03/ /06/1437 (04:00 PM) Duration: 60 minutes Marks: 15 Open Book Calculator Permitted Open Notes Laptop Permitted Student Name (in English): MODEL ANSWER Student ID: Section No.: Instructions: 1. Answer 3 questions; there are 3 questions in 5 pages. 2. Write your name on each page of the exam paper. 3. Write your answers directly on the question sheets. Use the ends of the question pages for rough work or if you need extra space for your answer. 4. If information appears to be missing from a question, make a reasonable assumption, state your assumption, and proceed. 5. No questions will be answered by the invigilator(s) during the exam period. Official Use Only Question Student Marks Question Marks Total 15 Imam University CCIS Doc. No Page 1 of 5

2 Question 1: Output To be answered in(15) Minutes [ ] / 4 Marks What is the output of the following codes? 1) int a = 1, b = 2, c = 3; bool r = true; if(r) cout<< b*(c/b)+c%b << endl; cout<< a - b / c * 10 <<endl; (2 marks) Output: 3 1 2) int x=3; (2 marks) do switch( x % 2) case 0: x-=2; break; case 1: x++; break; default: cout << "Unreachable statement"; cout << x << endl; while( x > 2 ); Output: 4 2 Imam University CCIS Doc. No Page 2 of 5

3 Question 2: Find and Fix Errors To be answered in(15) Minutes [ ] / 4 Marks Find and Fix the 4 errors in the following code. This code calculates the factorial of a given number. For each error, you should mention the complete wrong instruction, the type (syntax or logic), and the complete correct instruction. int main () int n; // int number; cout << "Enter a number : "; cin >> number ; cout << "The factorial of " << number << " is "; int accumulator = 0; // int accumulator = 1; for (int i = 1, i <= number, i++) // for (int i = 1 ; i <= number ; i++) accumulator * i; // accumulator *= i; cout << accumulator << ".\n"; Error 1 int n; Wrong Instruction // int accumulator = 0; 3 for (int i = 1, i <= number, i++) 4 accumulator * i; Error Type // 0.25 int number; Correct Instruction // 0.5 int accumulator = 1; for (int i = 1 ; i <= number ; i++) accumulator *= i; Imam University CCIS Doc. No Page 3 of 5

4 Question 3: Write a C++ Program To be answered in (30) Minutes [ ] /7 Marks You are assigned to write a C++ program that determines the biggest value and its number of occurrences from a list of strictly negative numbers greater than -250 provided by the user. Your program keep asking for numbers until the user enters a value out of the range, then it displays on the screen the count of entered numbers, the biggest value and its number of occurrences. Output sample 1: Provide a list of strictly negative numbers greater than -250: * n1 = 8 No correct value was entered. Output sample 2: Provide a list of strictly negative numbers greater than -250: * n1 = -8 * n2 = -74 * n3 = -8 * n4 = -52 * n5 = -85 * n6 = -2 * n7 = -78 * n8 = -2 * n9 = -32 * n10 = -2 * n11 = -270 You entered 10 number(s) The biggest value is -2 The biggest value occurs 3 time(s) Imam University CCIS Doc. No Page 4 of 5

5 int number, counter, max, occurrences; // 0.5 mark cout << "Provide a list of strictly negative numbers greater than -250:" <<endl; cout << " * n1 = "; cin >> number; // 0.5 mark max = number; // 0.5 mark counter = occurrences = 0; // 0.5 mark while (number < 0 && number > -250) // 1 mark counter++; // 0.25 mark if (max < number) // 0.75 mark max = number; occurrences = 1; else if (max == number) // 0.5 mark the user occurrences++; cout << " * n" << counter + 1 <<" = "; cin >> number; // 0.5 mark if (counter!= 0) // 1.5 mark cout << "You entered "<< counter << " number(s)" << endl; cout << "The biggest value is "<< max << endl; cout << "The biggest value occurs " << occurrences << " time(s)" << endl; else // 0.5 mark cout << "No correct value was entered" << endl; Imam University CCIS Doc. No Page 5 of 5