University:
University of California, Berkeley
Course:
COMPSCI 164 | Programming Languages and Compilers
Academic year:

2021
Views:

434

Pages:

8
Author:

sonalhava9qv

Chapter 6: User-Defined Functions TRUE/FALSE 1. Using functions greatly enhances a program’s readability because it reduces the complexity of the function main. ANS: T PTS: 1 REF: 336 2. Once you write and properly debug a function, you can use it in the program (or different programs) again and again without having to rewrite the same code repeatedly. ANS: T PTS: 1 REF: 340 3. If the formal parameter list of a function is empty, the parentheses after the function name are not needed. ANS: F PTS: 1 REF: 344 4. The following function heading in a C++ program is valid: int funcExp(int u, char v, float g) ANS: T PTS: 1 REF: 344 5. The data type of a variable in a return statement must match the function type. ANS: T PTS: 1 REF: 344 6. The execution of a return statement in a user-defined function terminates the program. ANS: F PTS: 1 REF: 345 7. In C++, a function prototype is the function heading without the body of the function. ANS: T PTS: 1 REF: 348 8. Assume that all variables are properly declared. The following statement in a value-returning function is legal. if (x % 2 == 0) return x; else return x + 1; ANS: T PTS: 1 REF: 351 9. The following return statement returns the value 10. return 10, 16; ANS: F PTS: 1 REF: 351 10. The function main is always compiled first, regardless of where in the program the function main is placed. ANS: F PTS: 1 REF: 361 MULTIPLE CHOICE 1. The standard header file for the abs(x)function is ____. a. c. d. b. ANS: A PTS: 1 REF: 337 2. To use the predefined function tolower, the program must include the header file ____. a. c. d. b. ANS: A PTS: 1 REF: 338 3. The output of the statement: cout << tolower('$') << endl; is ____. a. b. c. d. '$' '0' '1' An error, because you cannot use tolower with '$'. ANS: A PTS: 1 REF: 338 4. Assume the following. static_cast('a') = 97 static_cast('A') = 65 The output of the statement: cout << static_cast(tolower('B')) << endl; is ____. a. 65 c. 96 b. 67 d. 98 ANS: D PTS: 1 REF: 338 5. The output of the statement: cout << pow(3.0, 2.0) + 5 << endl; is ____. a. 11.0 b. 12.0 ANS: D c. 13.0 d. 14.0 PTS: 1 REF: 338 6. The output of the statement: cout << pow(2.0, pow(3.0, 1.0)) << endl; is ____. a. 6.0 b. 7.0 ANS: C c. 8.0 d. 9.0 PTS: 1 REF: 338 7. Functions that do not have a return type are called ____ functions. a. zero c. void b. null d. empty ANS: C PTS: 1 REF: 341 8. The heading of the function is also called the ____. a. title c. function head b. function signature d. function header ANS: D PTS: 1 REF: 341 9. A variable or expression listed in a call to a function is called the ____. a. formal parameter c. data type b. actual parameter d. type of the function ANS: B PTS: 1 REF: 342 10. A variable listed in a header is known as a(n) ____ parameter. a. actual c. formal b. local d. function ANS: C PTS: 1 REF: 342 11. Given the following function: int next(int x) { return (x + 1); } what is the output of the following statement? cout << next(next(5)) << endl; a. 5 c. 7 b. 6 ANS: C d. 8 PTS: 1 REF: 347-348 12. Which statement below about prototypes and headers is true? a. Parameter names must be listed in the prototype, but not necessarily in the header. b. Prototypes end with a semicolon, but headers do not. c. Headers should come before prototypes. d. Headers end with a semicolon, but prototypes do not. ANS: B PTS: 1 REF: 349 13. Given the following function prototype: int test(float, char);, which of the following statements is valid? a. cout << test(12, &); b. cout << test("12.0", '&'); c. int u = test(5.0, '*'); d. cout << test('12', '&'); ANS: C PTS: 1 14. A function prototype is ____. a. a definition, but not a declaration b. a declaration and a definition ANS: C PTS: 1 REF: 349 c. a declaration, but not a definition d. a comment line REF: 349 15. Given the following function prototype: double tryMe(double, double);, which of the following statements is valid? Assume that all variables are properly declared. a. cin >> tryMe(x); b. cout << tryMe(2.0, 3.0); c. cout << tryMe(tryMe(double, double), double); d. cout << tryMe(tryMe(float, float), float); ANS: B PTS: 1 REF: 349-350 16. Given the function prototype: double testAlpha(int u, char v, double t); which of the following statements is legal? a. cout << testAlpha(5, 'A', 2); b. cout << testAlpha( int 5, char 'A', int 2); c. cout << testAlpha('5.0', 'A', '2.0'); d. cout << testAlpha(5.0, "65", 2.0); ANS: A PTS: 1 REF: 349-350 17. Given the function prototype: float test(int, int, int); which of the following statements is legal? a. cout << test(7, test(14, 23)); b. cout << test(test(7, 14), 23); c. cout << test(14, 23); d. cout << test(7, 14, 23); ANS: D PTS: 1 REF: 349-350 18. Which of the following function prototypes is valid? a. int funcTest(int x, int y, float z){} b. funcTest(int x, int y, float){}; c. int funcTest(int, int y, float z) d. int funcTest(int, int, float); ANS: D PTS: 1 REF: 349-350 19.Which of the following function prototypes is valid? a. int funcExp(int x, float v); b. funcExp(int x, float v){}; c. funcExp(void); d. int funcExp(x); ANS: A PTS: 1 REF: 349-350 20. Given the following function prototype: int myFunc(int, int);, which of the following statements is valid? Assume that all variables are properly declared. a. cin >> myFunc(y); b. cout << myFunc(myFunc(7, 8), 15); c. cin >> myFunc('2', '3'); d. cout << myFunc(myFunc(7), 15); ANS: B PTS: 1 REF: 349-350 21. The statement: return 8, 10; returns the value ____. a. 8 c. 18 d. 80 b. 10 ANS: B PTS: 1 REF: 351 22. The statement: return 37, y, 2 * 3; returns the value ____. a. 2 c. y d. 6 b. 3 ANS: D PTS: 1 REF: 351 23. The statement: return 2 * 3 + 1, 1 + 5; returns the value ____. a. 2 c. 6 d. 7 b. 3 ANS: C PTS: 1 24. Given the following function: int strange(int x, int y) { if (x > y) REF: 351 return x + y; else return x – y; } what is the output of the following statement? cout << strange(4, 5) << endl; a. -1 b. 1 ANS: A c. 9 d. 20 PTS: 1 REF: 351 25. What value is returned by the following return statement? int x = 5; return x + 1; a. 0 b. 5 ANS: C c. 6 d. 7 PTS: 1 REF: 351 COMPLETION 1. A(n) ____________________ parameter s a formal parameter that receives a copy of the content of the corresponding actual parameter. ANS: value PTS: 1 REF: 365 2. When you attach & after the dataType in the formal parameter list of a function, the variable following that dataType becomes a(n) ____________________ parameter. ANS: reference PTS: 1 REF: 365 3. A(n) ____________________ parameter is a formal parameter that receives the location (memory address) of the corresponding actual parameter. ANS: reference PTS: 1 REF: 365 4. ____________________ parameters are useful in three situations: • When the value of the actual parameter needs to be changed • When you want to return more than one value from a function • When passing the address would save memory space and time relative to copying a large amount of data ANS: Reference reference PTS: 1 REF: 372 5. If a formal parameter is a nonconstant reference parameter, during a function call, its corresponding actual parameter must be a(n) ____________________. ANS: variable PTS: 1 REF: 372 6. Stream variables (for example, ifstream and ofstream) should be passed by ____________________ to a function. ANS: reference PTS: 1 REF: 376 7. The ____________________ of an identifier refers to where in the program an identifier is accessible (visible). ANS: scope PTS: 1 REF: 386 8. If a function needs to return more than one value, as a rule of good programming style, you should change it to a(n) ____________________ function and use the appropriate reference parameters to return the values. ANS: void PTS: 1 REF: 386 9. ____________________ identifiers are not accessible outside of the function (block). ANS: Local PTS: 1 REF: 386 10. In C++, :: is called the ____________________. ANS: scope resolution operator PTS: 1 REF: 390 11. A variable for which memory is allocated at block entry and deallocated at block exit is called a(n) ____________________ variable. ANS: automatic PTS: 1 REF: 395 12. A variable for which memory remains allocated as long as the program executes is called a(n) ____________________ variable. ANS: static PTS: 1 REF: 395 13. The program that tests a function is called a(n) ____________________ program. ANS: driver PTS: 1 REF: 396 14. A function ____________________ is a function that is not fully coded. ANS: stub PTS: 1 REF: 398 15. The ____________________ of a function consists of the function name and its formal parameter list. ANS: signature PTS: 1 REF: 399