Lecture Questions Solutions - Programming Concepts - Java | CSCI 261, Exams of Computer Science

Download Lecture Questions Solutions - Programming Concepts - Java | CSCI 261 and more Exams Computer Science in PDF only on Docsity! CSCI261 Lecture Questions Simple C++ This worksheet is for your use during and after lecture. It will not be collected or graded, but I think you will find it a useful tool as you learn C++ and study for the exams. Explain all false answers for the “True or False” questions; in general, show enough work and provide enough explanation so that this sheet is a useful pre-exam review. I will be happy to review your answers with you during office-hours, via Email, or instant messaging. 1. All of our C++ programs will have a function named: A. begin B. EntryPoint C. main D. WinMain Solution: C 2. All C++ statements end with a(n): A. period B. semi-colon C. colon D. flourish Solution: B 3. (a) Write “This is a comment” as a comment in two different ways for C++. Solution: /*This is a comment */ and //This is a comment. (b) Write the aforementioned comment across multiple lines in C++. Solution: /∗ T h i s i s a comment ∗ / / / T h i s / / i s a / / comment 4. True or False: Indentation is required for the compiler to understand the logical structure of a C++ source listing. Solution: False. Indentation is to help humans visualize the structure of program logic. 5. True or False: Everything in a C++ source listing is translated to the computer program. Solution: False. Comments and indentation are ignored. 6. True or False: A computer program is the compiler and linker translation of only the program source listing. Solution: False. Pre-processor directives “import” code from system libraries. 7. Which of the following properties does a program variable possess? A. Size (in bits or bytes) B. Location (address in memory) C. URL (universal resource locator) D. Name E. Value CSCI261 Lecture Questions Simple C++ Solution: A, B, D, and E. 8. What is another name for the name given to a variable? Solution: An identifier. 9. List three examples of valid C++ variable names. Solution: x3, SuperMan, mighty_mouse 10. List two examples of invalid C++ variables names, and state why they are invalid. Solution: 3x: numerals cannot begin variable names. CO2%: The percent sign is an invalid character for variable names. 11. In the following table are four fundamental variables types in C++, list example values for each varible type. double 3.14, -1, 0, 32 int -3, 0, 256 string "c", "word", or "a phrase of several words" bool true, false 12. Which of the fundamental variable types in 11 require(s) a pre-processor directive and a compiler directive? What are they? Solution: The string type requires #include <string>, and using namespace std;. 13. Write two ways to declare a Boolean variable named truth as logical false. Solution: bool truth( false ); or bool truth = false;. 14. Write two ways to declare an integer variable named N with the value 3. Solution: int N( 3 ); or int N = 3;. 15. Write two ways to declare a constant real valued variable named PI as the value π. Solution: const double PI( acos(-1) ); or double PI = acos(-1);. 16. Assume the real valued variables x, y, and z are properly declared in a C++ program, complete the table by translating the mathematical expression to a C++ statement. Mathematical Expression C++ Statement x2 + y− 1z x*x + y - 1/z √ 3x−4y+ xzy sqrt( 3*x - 4*y) + x/(z*y) Page 2