True or False (14 Points)

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1 Name Number True or False (14 Points) 1. (15 pts) Circle T for true and F for false: T F a) void functions can use the statement return; T F b) Arguments corresponding to value parameters can be variables. T F c) Static variables retain their value from function call to function call. T F d) The memory address of the first element of an array is called the Base Address. T F e) The elements of a C++ array must be homogeneous T F f) Given the declaration int beta[20]; the statement cout << beta[20]; can be used to display all 20 elements of the array named beta on the standard output device. T F g) If a program has the declarations enum WeatherType SUNNY, CLOUDY, FOGGY, WINDY; int frequency[4]; then the statement cout << frequency[cloudy]; is syntactically valid. T F h) Local variables can be accessed outside of the block in which they are declared. T F i) A hierarchical structure has at least one member that is itself a structure. T F j) Global identifiers have name precedence over local identifiers. T F k) The names of members in a structure must be unique for that structure T F l) The expression name.first is used to access the name member of the structure variable first. T F m) C++ does not check for out-of-bounds array indexes at compile time. T F n) The lifetime of a local variable is for the duration of the program. Page 1 of 12

2 Extra Credit #1 (2 pts) The code from class on 11/2/17 is: (must have signed the sheet) A) 123ABC B) 789XYZ C)ABCXYZ D)Exam 3 Extra Credit #2 (2 pts) What is the answer to the following equation: 9 3 1? A)1 B)3 C)7 D)9 E)19 Multiple choice (16 points) Questions 2 17 For these problems circle all correct answers. For example if answers A, C and E are all valid then circle A, C and E. 2. How many function values does a value-returning function have? A) 4 B) 2 C) As many as necessary D) 1 E) 3 F) None of these 3. A function that does not return a function value is known as what kind of function? A) Value returning function B) Reference Parameter C) Empty D) Void function E) Expression less F) None of these 4. Circle all operations that ARE ALLOWABLE aggregate operations on structures. A) Input/Output (cin, cout statements) B) Assignment C) Arithmetic D) Return as a functions return value E) Comparison F) Argument pass by value to a function G) Argument pass by reference to a function 5. Circle all operations that ARE ALLOWABLE aggregate operations on arrays. A) Input/Output (cin, cout statements) B) Assignment C) Arithmetic D) Return as a functions return value E) Comparison F) Argument in a function call G) All of the above (a through f) Page 2 of 12

3 6. Reference parameters (passing by reference) are used if a parameters data flow is: A) One-way, into the function B) One-way, out of the function C) Two-way, into and out of the function D) None of these 7. Value parameters (passing by value) are used if a parameters data flow is: A) two-way, into and out of the function B) one-way, into the function C) one-way, out of the function D) None of these 8. Which parameters in the following function heading are value parameters? void DoSomething(string date, int& num, float average, float& sum, string name) A) date B) num C) average D) sum E) name F) None of them 9. Which parameters in the following function heading are reference parameters? void DoSomething(string& month, int& day, float cost, float pay, string year) A) month B) day C) cost D) pay E) year F) None of them 10. The following code fragment invokes (calls) a void function named InitToZero: int alpha[20]; InitToZero(alpha); // returns alpha with every element of the array set to 0 Which of the following is a valid function heading for InitToZero? A) void InitToZero( const int beta ) B) void InitToZero( int beta[20] ) C) void InitToZero( int [20] ) D) None of These 11. For the function InitToZero described above in Problem 10, which of the following would be an appropriate function prototype? A) void InitToZero( const int [20] ); B) void InitToZero( const int ); C) void InitToZero( int [ ] ); D) None of These Page 3 of 12

4 12. Suppose that typedef int MatrixType[MAXROWS][MAXCOLS]; has been used to create a two-dimensional array matrix data type called MatrixType. Which of the following statements correctly declares a variable named C of the data type MatrixType? A) MatrixType[MAXROWS][MAXCOLS] C; B) MatrixType C; C) int MatrixType; D) None of These 13. Given the global type declaration MatrixType as described in problem 13, which of the following would be a suitable function prototype for a function named PrintMatrix? A) void PrintMatrix( MatrixType[ ][ ] ); B) void PrintMatrix( MatrixType M ); C) void PrintMatrix( MatrixType M[MAXROWS][ ]); D) None of These 14. Which of the following statements correctly declares a one-dimensional array variable named somearray with exactly 9 elements of type int? A) int somearray[8]; B) int somearray[9]; C) int somearray[10]; D) typedef int somearray[9]; E) B and D F) None of these 15. A function SomeFunc has two parameters, alpha and beta, of type int. The data flow for beta is one-way, into the function. The data flow for alpha is two-way, into and out of the function. What is the most appropriate function heading for SomeFunc? (One answer only) A) void SomeFunc(int alpha, int beta) B) void SomeFunc(int& alpha, int beta) C) void SomeFunc(int& alpha, int& beta) D) void SomeFunc(int alpha, int& beta) E) None of the above Page 4 of 12

5 16. The function PrintMatrix will work only for 2x2 matrices. Assuming that the matrix dimensions are represented by global integer constants MAXROWS and MAXCOLS which specify the maximum number of rows and columns, respectively, in the matrix M, which of the following code fragments would correctly print out the contents of the matrix M row-by-row? If matrix M were as follows: M Sample output for matrix M: A) int r,c; B) int r,c; for(c=0; c<maxcols; c++) for(r=0; r<=maxrows; r++) for(r=0; r<maxrows; r++) for(c=0; c<=maxcols; c++) cout << M[r][c] ; cout << M[r][c] ; cout << endl; cout << endl; C) int r,c; D) int r,c; for(c=1; c<maxcols; c++) for(r=0; r<maxrows; r++) for(r=1; r<maxrows; r++) for(c=0; c<maxcols; c++) cout << M[r][c] ; cout << M[r][c] ; cout << endl; cout << endl; E) None of the above produces the desired output 17. Assuming that the one-dimensional array variable somearray has already been declared to hold 10 integers. Suppose that one wishes to initialize each array element to its index value ( the array element holds the value of the index necessary to access that element ) Which of the following program fragments correctly initializes the array somearray? A) int k = 1; B) int k = 0; C) int k = 0; while (k <= 10) while (k <= 9) while (k <= 9) somearray[k]=k; somearray[k]=k; k=somearray[k]; k++; ++k; ++k; D) int k = 0; E) int k = 0; F) None of these while (k < 9) while (k < 10) somearray[k] = k; somearray[k] = k; k++; k++; Page 5 of 12

6 Short Answer (70 points) Questions (8 pts) When the program shown below is executed, what is the output to the screen? This problem deals with the scope of a variable in a program, and the order of execution of statements. #include <iostream> using namespace std; void function_a(int); void function_b(int&); int number = 3; // global variable declaration of number int main() int number = 5; cout << number in main is: << number << endl; function_b(number); function_a(number); return 0; void function_a(int number) number = number + 2; cout << number in function A is: << number << endl; void function_b(int& sum) sum = sum - 3; cout << sum in function B is: << sum << endl; cout << number in function B is: << number << endl; The identifying phrases written by the cout statements in this program are shown below. In the blank to the left of the lines, place 1,2,3 or 4 to indicate the order the statements are printed (1 for first, 4 for last). The value output is placed in the blank at the end of the line. number in main is: number in function A is: number in function B is: sum in function B is: Page 6 of 12

7 19. (8 pts) For the following code segment, write out what is printed to the screen. Show the displayed output precisely by using the following rules: o Write one character per box. o Skip a box to indicate the presence of a blank space in the output. o Skip a row to indicate the presence of a blank line in the output. #include <iostream> using namespace std; void Test(); int main() Test(); Test(); Test(); Test(); return 0; void Test() static int i = 10; static int j = 0; i = i - 2; j = j + 2; cout << i << << j << endl; Page 7 of 12

8 20. (4 pts) Consider the following structure declaration when answering the questions below. struct University string nickname; // nickname of the university int undergrads; // number of under graduate students int grads; // number of graduate students int alumni; // number of alumni ; a) Write a statement that declares the identifier UAH as a structure variable of DataType University. b) Write a cout statement that will output the value of the member grads of the structure variable UAH. c) Write a cout statement that will output the value of the member nickname of the structure variable UAH. d) Write a statement that assigns a value of Chargers to the nickname member of UAH. 21. (4 pts) Write the type declaration for a struct DataType named Counters containing the following members: - an integer variable representing the number of letters - an integer variable representing the number of digits - an integer variable representing the number of lines - a string variable indicating the name of the counter Page 8 of 12

9 22. (10 pts) For the questions A through G, consider the following program. Note just the lines of importance have been displayed here. There is at least one answer for each question, and some may have more than one answer. Provide ALL the answers to a question. As an example, if the question is what line contains a return statement? The answer is line 12, 14, 16 and line 18. #include <iostream> // Line 1 using namespace std; // Line 2 int function_1(int&, float, int); // Line 3 void function_2(float&, int, float&); // Line 4 void function_3(); // Line 5 int main() // Line 6 int sum1, num, enter; // Line 7 float temp, avg; // Line 8 function_3(); // Line 9 function_2(avg,num,temp); // Line 10 function_2(avg,function_1(sum1,avg,num),temp); // Line 11 return 0; // Line 12 int function_1(int& sum, float number, int enter) // Line 13 return enter; // Line 14 void function_2(float& average, int count, float& number) // Line 15 return; // Line 16 void function_3() // Line 17 return; // Line 18 A) Which of the lines indicated are function prototypes? B) Which of the lines indicated include function calls? C) Which lines are a function heading? D) What are the arguments used in the function call for function_1? E) Which parameter(s) of function_2 are value parameters? Page 9 of 12

10 23. (12 pts) What is the output for the following program? Pay attention to the index values used with the arrays. #include <iostream> using namespace std; void init_array (int[][3]); void print_array (int [][3]); int main() int my_array[4][3]; init_array(my_array); print_array(my_array); return 0; void init_array (int my_array[][3]) int row, col; for (row = 0; row < 4 ; row++) for (col = 0; col < 3; col++) my_array[row][col] = row + col; void print_array (int my_array[][3]) int row, col; for (row = 3; row >= 0; row--) for (col = 2; col >= 0; col--) cout << my_array[row][col] << ; cout << endl; Page 10 of 12

11 24. (12 pts) Finish the program below by adding a void function as specified below. Add only a function prototype, function call statement and function definition to the following program. Do not add any variable declarations. The name of the void function is InitStruct. The function has one parameter of the structure DataType Date. The function is to initialize the structure parameter with a date of January 1, 2000 The information stored in the parameter must be available in main() after the function call. #include <iostream> using namespace std; struct Date // format of the date is Month Day, Year // where day and year are numeric, Month is the month name int day; int year; string Month; ; // Place the function prototype below this line int main() Date day; // day is a structure variable of data type Date // Place the function call below this line return 0; // Place the function definition below this line Page 11 of 12

12 25. (12 pts) Add a function prototype, function call statement and function definition to the following program. The name of the void function that is to be added is FillArray. This function is to read in values from standard input (cin) to fill all of the array elements. The void function has the following two parameters: 1) An integer one-dimensional array, 2) an integer value representing the number of array elements to read in. In the function definition use a for loop to read in a value for each element/component of the array. Use cout to prompt for a value and cin for reading the value. Assume that all values are entered correctly. #include <iostream> using namespace std; const int NUM = 1000; // dimension size: number of values to read // Place the function prototype below this line int main() int numbers[num]; // one-dim. Array for holding integers entered // Place the function call statement below this line return 0; // Place the function definition below this line Page 12 of 12

True or False (15 Points)

Name Number True or False (15 Points) 1. (15 pts) Circle T for true and F for false: T F a) Value Returning Functions cannot use reference parameters. T F b) Arguments corresponding to value parameters