CS 1044 Programming in C++ Test 1 Spring 2011 Form B Page 1 of 12 READ THIS NOW!

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1 Spring 2011 Form B Page 1 of 12 READ THIS NOW! Failure to read and follow the instructions below may result in severe penalties. Failure to adhere to these directions will not constitute an excuse or defense. Print your name & address in the spaces provided below. Print your name and Va Tech ID number (NOT your SSN) on the Opscan form; be sure to code your ID number on the Opscan form. Code Form B on the Opscan. Choose the single best answer for each question some answers may be partially correct. If you mark more than one answer, it will be counted wrong. Unless a question involves determining whether given C++ code is syntactically correct, assume that it is. The given code has been compiled and tested, except where there are deliberate errors. Unless a question specifically deals with compiler #include directives, you should assume the necessary header files have been included. Note that questions about printed values disregard formatting completely. In questions/answers which require a distinction between integer and real values, integers will be represented without a decimal point, whereas real values will have a decimal point, [ 1044 (integer), (real)]. When you have finished, sign the pledge at the bottom of this page and turn in the test and your Opscan. This is a closed-book, closed-notes examination. No calculators or other electronic devices may be used during this examination. You may not discuss (in any form: written, verbal or electronic) the content of this examination with any student who has not taken it. You must return this test form when you complete the examination. Failure to adhere to any of these restrictions is an Honor Code violation. Mark your answers on the test form, for future reference, and on the Opscan. The answers you mark on the Opscan form will be considered your official answers. There are 35 multiple-choice questions. Do not start the test until instructed to do so! Name VT (print: Last name, (print: campus address) Pledge: On my honor, I have neither given nor received unauthorized aid on this examination. signature

2 Fall 2011 Form B Page 2 of 12 For the next eight questions, consider writing a program that is to read data records consisting of: The name of a computer processor unit (CPU), followed immediately by a tab, then The model of the processor, followed immediately by a tab, then A double representing the giga-hertz clock cycle, followed immediately by a tab, then An integer representing the PaasMark benchmark score, followed immediately by a newline. The name of the input is file, "cpus.txt", the first two lines contains labels. An incomplete example follows: #Computer processor benchmark results #name model speed-ghz PassMark Intel Core i7 995X Intel Xeon W Intel Core i7 2600K AMD Opteron 6176SE AMD Six-Core xxxx Assume that the necessary header files have been included in the program. The program below must read through the data lines and compute the average CPU speed and PassMark score. CPUs with a speed of 0.0 have an unknown speed and must not be computed in the CPU speed average. Consider the following partial implementation of code to solve this problem: int main() { int numcpus = 0, speedcount = 0, passscore, totalpassmarks = 0; double speed, avgspeed, avgpassmark, sumspeeds = 0.0; ifstream ifile; ifile.open("cpus.txt"); // Input the first data line // Task 0: skip the first two label lines // Task 1: skip the processor name while ( ifile ) { // Task 2: skip the processor model // Task 3: input the processor speed // Task 4: input the processor pass mark score // Task 5: update the count of the number of CPUs input // Task 6: update the speed count of CPUs with positive speeds // Task 7: keep a running subtotal of the CPU speeds // Task 8: keep a running subtotal of the CPU pass mark scores // Task 9: skip to the next input dataline // Task 10: skip the processor name }//endwhile ifile.clear(); if ( numcpus > 0 ) // Task 11: compute the average pass mark score // Task 12: output the average pass mark score if (speedcount > 0 ) // Task 13: compute the average CPU speed in GHz // Task 14: output the average CPU speed (GHz) } return EXIT_SUCCESS;

3 Fall 2011 Form B Page 3 of 12

4 Fall 2011 Form B Page 4 of 12 1) Which of the following code fragments will properly carry out Task 1, (skip the processor name)? 1) ifile << speed; 2) ifile >> speed; 3) getline(ifile, speed); 4) getline(ifile, speed, '\t'); 5) ifile.ignore( 20, \t ); 6) 1 and 3 only 7) 2 and 3 only 8) 1 and 4 only 9) 2 and 4 only 10) None of these 2) Assuming correct solutions to the tasks 1-2, which of the following code fragments will then properly carry out Task 3, (input the processor speed)? 1) ifile << speed; 2) ifile >> speed; 3) getline(ifile, speed); 4) getline(ifile, speed, '\t'); 5) ifile >> speed >> '.' >> speed; 6) 1 and 3 only 7) 2 and 3 only 8) 1 and 4 only 9) 2 and 4 only 10) None of these 3) Assuming correct solutions to the tasks 1-4, which of the following code fragments will then properly carry out Task 5, (update the count of the number of CPUs input)? 1) numcpus++; 2) --numcpus; 3) numcpus = numcpus + speed 4) numcpus = speed + 1; 5) 1 and 3 only 6) 3 and 4 only 7) All of these 8) None of these 4) Assuming correct solutions to tasks 1-5, which of the following code fragments will then properly carry out Task 6, (update the speed count of CPUs with positive speeds)? 1) ++speedcount; 2) if (speed > 0.0) speedcount++; 3) if (passscore > 0) speedcount++; 4) if (numcpus > 0) speedcount++; 5) All of these 6) 1 and 3 only 7) 2 and 3 only 8) 1 and 4 only 9) None of these

5 Fall 2011 Form B Page 5 of 12 5) Assuming correct solutions to tasks 1-6, which of the following code fragments will then properly carry out Task 7, (keep a running subtotal of the CPU speeds)? 1) sumspeeds = speed; 2) sumspeeds++; 3) sumspeeds = sumspeeds + speed; 4) speed = speed + sumspeeds; 5) All of these 6) 1 and 2 only 7) 1 and 4 only 8) 2 and 3 only 9) None of these 6) Assuming correct solutions to tasks 1-7, which of the following code fragments will then properly carry out Task 8, (keep a running subtotal of the CPU pass mark scores)? 1) totalpassmarks++; 2) totalpassmarks = passscore; 3) passscore = totalpassmarks + passscore; 4) totalpassmarks = totalpassmarks + passscore; 5) passscore++; 6) passscore = totalpassmarks; 7) 1 and 3 only 8) 2 and 4 only 9) 3 and 5 only 10) None of these 7) Assuming correct solutions to tasks 1-10, which of the following code fragments will then properly carry out Task 11, (compute the average pass mark score)? Hint: select the best answer. 1) avgpassmark = passscore / numcpus; 2) avgpassmark = passscore / totalpassmarks; 3) avgpassmark = passscore / double(totalpassmarks); 4) avgpassmark = totalpassmarks / numcpus; 5) avgpassmark = totalpassmarks / double(numcpus); 6) avgpassmark = totalpassmarks / double(passscore); 7) 1 and 3 only 8) 2 and 4 only 9) 3 and 5 only 10) None of these

6 Fall 2011 Form B Page 6 of 12 8) Assuming correct solutions to tasks 1-12, which of the following code fragments will then properly carry out Task 13, (compute the average CPU speed in GHz)? 1) avgspeed = speed / speedcount; 2) avgspeed = sumspeeds / speedcount; 3) avgspeed = speed / numcpus; 4) avgspeed = sumspeeds / numcpus; 5) avgspeed = avgspeed / numcpus; 6) avgspeed = avgspeed / speedcount; 7) 1 and 3 only 8) 2 and 4 only 9) 3 and 5 only 10) None of these 9) What output would the following code fragment produce? int Value = 42; cout << " " << endl; cout << setw(10) << setfill(' ') << Value << setw(10) << setfill('.') << Value; 1) ) ) ) ) None of these 10) What output would the following code fragment produce? int TotalInCents = 4209; int Dollars = TotalInCents / 100; int Cents = TotalInCents % 100; cout << " " << endl; cout << setw(7) << setfill(' ') << Dollars << setw(2) << setfill('0') << Cents; 1) ) ) ) ) None of these

7 Spring 2011 Form B Page 7 of 12 Consider the following simple polynomial: f(x) = 3x 3 + 2x 2 + x Given the following C++ variable declarations: double fn, //the function of x x; 11) Assume that x has been assigned a value. Which one of the following lines of code accurately assigns the fn to the correct computation of the above polynomial? 1) fn = 3x^3 + 2x^2 + x; 2) fn = 3*x^3 + 2*x^2 + x; 3) fn = 3*x**3 + 2*x**2 + 1*x**x; 4) fn = x * ( x * ( 3 * x + 2 ) + 1 ); 5) None of the above For the following 5 questions, suppose the (file) input stream infile contains the following 5 lines of data (there's several blank characters between columns and a newline character immediately after the last character on each line): Oct Sky Rocket Boys Hickam What is the value of each of the indicated variables after the execution of the following program segment? int zero = 0, one = 1, two = 2, three = 3, four =4; infile >> zero >> zero; infile.ignore(100, '\n'); infile.ignore(100, '\n'); infile >> one >> two >> three >> four; infile.ignore(100, '\n'); infile >> three >> three >> three >> three; infile.ignore(100, '\n'); if (infile) infile >> four; ) zero none of the above 13) one none of the above 14) two none of the above 15) three none of the above 16) four none of the above

8 Spring 2011 Form B Page 8 of 12 17) Give the output that would be produced by the following C++ code: int x = 1; int y = 2; if ( x / y == x ) if ( x % y == x) cout << x; else cout << y; 1) 1 2) 2 3) no output For each of the following 6 questions, assume the following C++ declarations and assignments: int a = 2, b = 5, c = 8, d = 12, e = 23, f = 28; double g = 2.4, h = 5.0; 18) Which of the following expressions would result in the output of the value: 4 1) cout << f / e - b ; 2) cout << c % a ; 3) cout << b / a * a ; 4) cout << c - d + b ; 19) Which of the following expressions would result in the output of the value: 27 1) cout << c + a b * b ; 2) cout << f e + d / a ; 3) cout << c - a + b / b ; 4) cout << f + e - d * a ; 20) Which of the following expressions would result in the output of the value: 3 1) cout << a % b ; 2) cout << b % a ; 3) cout << b % e ; 4) cout << e % b ; 21) Which of the following expressions would result in the output of the value: 25 1) cout << b ^ a ; 2) cout << b ** a ; 3) cout << f ^ (a-1) - a; 4) cout << f ** (a-1) - a;

9 Spring 2011 Form B Page 9 of 12 22) Which of the following expressions would result in the output of the value: 2.4 1) cout << d / h ; 2) cout << g - a ; 3) cout << e / h - a; 4) cout << h - g; 23) Which of the following expressions would result in the output of the value: 2.5 1) cout << b / a ; 2) cout << b / a 0.0 ; 3) cout << g + h / 10; 4) cout << d / ; For the next four questions, consider execution of the following code fragment: bool A, B, C, D; // code that assigns values to A, B, C, and D if (!A B ) if (!C && D ) cout << "one" << endl; else if (D) cout << "two" << endl; else cout << "three" << endl; else if (!C &&!D ) cout << "four" << endl; else if (D) cout << "five" << endl; else cout << "six" << endl; 24) What of the following sets of values for A, B, C, and D would cause the string "one" to be printed? A B C D 1) true false true true 2) true true true false 3) true false false true 4) true true false false 5) false false true true 6) false true true false 7) false false false true 8) false true false false 9) None of these

10 Spring 2011 Form B Page 10 of 12 25) What of the following sets of values for A, B, C, and D would cause the string "three" to be printed? A B C D 1) true false true true 2) true true true true 3) true false false true 4) true true false false 5) false false true true 6) false true true false 7) false false false true 8) false true false false 9) None of these 26) What of the following sets of values for A, B, C, and D would cause the string "four" to be printed? A B C D 1) true false true true 2) true true true true 3) true false false true 4) true true false false 5) false false true true 6) false true true false 7) false false false true 8) true false false false 9) None of these 27) What of the following sets of values for A, B, C, and D would cause the string "six" to be printed? A B C D 1) true false true false 2) true true true true 3) true false false true 4) true true false false 5) false false true true 6) false true true false 7) false false false true 8) true false false false 9) None of these 28) Where will the cpp file be located for a C++ program executed under MS Visual C++ Express by default? 1) the project folder 2)the project folder name under the project folder 3) the debug folder under the project folder 4) the debug folder under the project folder under the project folder

11 Spring 2011 Form B Page 11 of 12 29) Which of the following types of MS Visual C++ Express projects are used in this course? 1) 2) 3) 4) 30) Which of the following is NOT a category of programming errors? 1) Syntax 2) Compilation 3) Linking 4) Execution 5) Runtime 6) All of the above are categories of programming errors. For the next two questions, assume that the input file Data.txt is: 31) What output would the following code fragment produce? ifstream In; In.open("Data.txt"); char Value; In.ignore(12, '\n'); In >> Value; cout << "Value: " << Value << endl; 1) Value: 1 2) Value: 2 3) Value: 3 4) Value: 4 5) Value: 5 6) Value: 6 7) Value: 7 8) Value: 8 9) Value: 9 10) Value: 0 32) What output would the following code fragment produce? ifstream In; In.open("Data.txt"); char Value; In.ignore(2323, '9'); In >> Value; cout << "Value: " << Value << endl; 1) Value: 1 2) Value: 2 3) Value: 3 4) Value: 4 5) Value: 5 6) Value: 6 7) Value: 7 8) Value: 8 9) Value: 9 10) Value: 0

12 Spring 2011 Form B Page 12 of 12 33) An output file that does not contain all of the data written to it by an associated C++ ofstream after the program has completed execution is usually the result of which of the following? 1) The ofstream NOT being opened. 2) The ofstream NOT being closed. 3) The ofstream NOT having showpoint and fixed inserted into it. 4) none of the above For the next two questions select from the following responses: 1) syntax/compilation 2) linking 3) execution / runtime 4) logic 34) Which of the types of programming errors is the responsibility of the programmer to detect? 35) Which of the types of programming errors is due to a violation of the grammar of the language?

CS 1044 Programming in C++ Test 1 READ THIS NOW! Failure to read and follow the instructions below may result in severe penalties.

CS 1044 Programming in C++ Test 1 READ THIS NOW! Failure to read and follow the instructions below may result in severe penalties. READ THIS NOW! Failure to read and follow the instructions below may result in severe penalties. Print your name in the space provided below. Print your name and ID number on the Opscan form and code your