Final Exam C++ Part 2

inFile.open("progdata.dat");

Consider the following program segment. ifstream inFile; //Line 1 int x, y; //Line 2 ... //Line 3 inFile >> x >> y; //Line 4 Which of the following statements at Line 3 can be used to open the file progdata.dat and input data from this file into x and y at Line 4?

Pass

Consider the following statements. int score; string grade; if (score >= 65) grade = "pass"; else grade = "fail"; If score is equal to 75, the value of grade is "____________________".

False

In C++, !, &&,and || are called relational operators. TRue or False

True

In C++, && has a higher precedence than ||. True or False

False

In C++, both ! and != are relational operators. True or False

member access

In C++, the dot is an operator called the ____ operator.

Member access

In C++, the dot is an operator called the ____________________operator.

Selection

In a ____ control structure, the computer executes particular statements depending on some condition(s).

False

In an output statement, each occurrence of endl advances the cursor to the end of the current line on an output device. True or False

False

In the statement cin >> x;, x can be a variable or an expression. True or False

alpha = 17, ch = 'A'

Suppose that alpha is an int variable and ch is a char variable and the input is: 17 A What are the values after the following statements execute? cin >> alpha; cin >> ch;

300

Suppose that alpha, beta, and gamma are int variables and the input is: 100 110 120 200 210 220 300 310 320 What is the value of gamma after the following statements execute? cin >> alpha; cin.ignore(100, '\n'); cin >> beta; cin.ignore(100,'\n'); cin >> gamma;

X

Suppose that ch1 and ch2 are char variables and the input is: WXYZ What is the value of ch2 after the following statements execute? cin >> ch1; ch2 = cin.peek(); cin >> ch2;

w

Suppose that ch1 and ch2 are char variables and the input is: WXYZ What is the value of ch2 after the following statements execute? cin.get(ch1); cin.putback(ch1); cin >> ch2;

ch1 = 'A', ch2 = ' ', alpha = 18

Suppose that ch1 and ch2 are char variables, alpha is an int variable, and the input is: A 18 What are the values after the following statement executes? cin.get(ch1); cin.get(ch2); cin >> alpha;

'C'

Suppose that ch1, ch2, and ch3 are variables of the type char and the input is: A B C Choose the value of ch3 after the following statement executes: cin >> ch1 >> ch2 >> ch3;

'B'

Suppose that ch1, ch2, and ch3 are variables of the type char and the input is: A B C What is the value of ch3 after the following statements execute? cin.get(ch1); cin.get(ch2); cin.get(ch3);

outFile.open("outputData.out");

Suppose that outFile is an ofstream variable and output is to be stored in the file outputData.out. Which of the following statements opens the file outputData.out and associates outFile to the output file?

1565.683 85.7800 123.98

Suppose that x = 1565.683, y = 85.78, and z = 123.982. What is the output of the following statements? cout << fixed << showpoint; cout << setprecision(3) << x << ' '; cout << setprecision(4) << y << ' ' << setprecision(2) << z << endl;

25.67 356.88 7623.97

Suppose that x = 25.67, y = 356.876, and z = 7623.9674. What is the output of the following statements? cout << fixed << showpoint; cout << setprecision(2); cout << x << ' ' << y << ' ' << z << endl;

55.680 476.859 23.82

Suppose that x = 55.68, y = 476.859, and z = 23.8216. What is the output of the following statements? cout << fixed << showpoint; cout << setprecision(3); cout << x << ' ' << y << ' ' << setprecision(2) << z << endl;

This statement results in input failure

Suppose that x and y are int variables, ch is a char variable, and the input is: 4 2 A 12 Choose the values of x, y, and ch after the following statement executes: cin >> x >> ch >> y;

x = 28, y = 32, z = 0.6

Suppose that x and y are int variables, z is a double variable, and the input is: 28 32.6 12 Choose the values of x, y, and z after the following statement executes: cin >> x >> y >> z;

cin >> x >> y;

Suppose that x and y are int variables. Which of the following is a valid input statement?

x = 10, y = 20.7

Suppose that x is an int variable and y is a double variable and the input is: 10 20.7 Choose the values after the following statement executes: cin >> x >> y;

ch = '2', x = 76

Suppose that x is an int variable, ch is a char variable, and the input is: 276. Choose the values after the following statement executes: cin >> ch >> x;

x = 15, ch = 'A', y = 73.2

Suppose that x is an int variable, y is a double variable and ch is a char variable and the input is: 15A 73.2 Choose the values after the following statement executes: cin >> x >> ch >> y;

True

The number of input data extracted by cin and >> depends on the number of variables appearing in the cin statement. True or False

True

The operators != and == have the same order of precedence. True or False

False

The result of a logical expression cannot be assigned to an int variable, but it can be assigned to a bool variable True or False

short-circuit evaluation

The term ____________________ describes a process in which the computer evaluates a logical expression from left to right and stops as soon as the value of the expression is known.

False

The value of the expression 6 < 5 || 'g' > 'a' && 7 < 4 is ____________________.

True

The value of the expression 7 + 8 <= 15 is ____________________.

break

To output results correctly, the switch structure must include a(n) ____________________ statement after each cout statement, except the last cout statement.

less than or equal to

What does <= mean?

35 45 10

What is the output of the following C++ code? int x = 35; int y = 45; int z; if (x > y) z = x + y; else z = y - x; cout << x << " " << y << " " << z << endl;

2

What is the output of the following C++ code? int x = 55; int y = 5; switch (x % 7) { case 0: case 1: y++; case 2: case 3: y = y + 2; case 4: break; case 5: case 6: y = y - 3; } cout << y << endl;

Section 5

What is the output of the following code? char lastInitial = 'S'; switch (lastInitial) { case 'A': cout << "section 1" <<endl; break; case 'B': cout << "section 2" <<endl; break; case 'C': cout << "section 3" <<endl; break; case 'D': cout << "section 4" <<endl; break; default: cout << "section 5" <<endl; }

123456789012345678901234567890 ####Mickey Donald*****Goofy

What is the output of the following statements? cout << "123456789012345678901234567890" << endl cout << setfill('#') << setw(10) << "Mickey" << setfill(' ') << setw(10) << "Donald" << setfill('*') << setw(10) << "Goofy" << endl;

12345678901234567890 ***18**Happy**Sleepy

What is the output of the following statements? cout << setfill('*'); cout << "12345678901234567890" << endl cout << setw(5) << "18" << setw(7) << "Happy" << setw(8) << "Sleepy" << endl;

True

A compound statement functions as if it was a single statement. True or False

True

A control structure alters the normal sequential flow of execution in a program. True or False

True

Suppose P and Q are logical expressions. The logical expression P && Q is true if both P and Q are true. True or False

False

Suppose found = true and num = 6. The value of the expression (!found) || (num > 6) is ____________________.

2

Assume you have three int variables: x = 2, y = 6, and z. Choose the value of z in the following expression: z = (y / x > 0) ? x : y;.

Predefined

C++ comes with a wealth of functions, called ____________________ functions, that are written by other programmers.

Classes

C++ has a special name for the data types istream and ostream. They are called ____________________.

fstream

C++ provides a header file called ____________________, which is used for file I/O.

True

Entering a char value into an int variable causes serious errors, called input failure. True or False

#include <cassert>

For a program to use the assert function, it must include which of the following?

False

If input failure occurs in a C++ program, the program terminates immediately and displays an error message. True or False

False

If the expression in an assert statement evaluates to true, the program terminates. True or False

False

It is a good idea to redefine cin and cout in your programs. True or False

iostream

Manipulators without parameters are part of the ____ header file.

Fail

Once an input stream enters a(n) ____________________ state, all subsequent input statements associated with that input stream are ignored, and the computer continues to execute the program, which produces erroneous results.

!

Putting ____________________ in front of a logical expression reverses the value of that logical expression.

Semantic

Putting a semicolon after the parentheses following the expression in an ifstatement (that is, before the statement) is a(n) ____________________ error.

x = 15, y = 76.3, z = 14

Suppose that x is an int variable, y is a double variable, z is an int variable, and the input is: 15 76.3 14 Choose the values after the following statement executes: cin >> x >> y >> z;

(x > 0) || ( x <= 0)

Suppose that x is an int variable. Which of the following expressions always evaluates to true?

True

Suppose x is 5 and y is 7. Choose the value of the following expression: (x != 7) && (x <= y)

Associativity

The ____________________ of relational and logical operators is said to be from left to right.

True

The expression (x >= 0 && x <= 100) evaluates to false if either x < 0 or x >= 100. True or False

decision maker

The expression in an if statement is sometimes called a(n) ____.

False

The extraction operator >> skips only all leading blanks when searching for the next data in the input stream. True or False

False

The following statements will result in input failure if the input values are not on a separate line. (Assume that x and y are int variables.) cin >> x; cin >> y; True or False

peek

The function ____________________ returns the next character in the input stream; it does not remove the character from the input stream.

4

What is the value of x after the following statements execute? int x; x = (5 <= 3 && 'A' < 'F') ? 3 : 4

nested

When one control statement is located within another, it is said to be ____.

True

When reading data into a char variable, after skipping any leading whitespace characters, the extraction operator >> finds and stores only the next character; reading stops after a single character. True or False

Ignore

When you want to process only partial data, you can use the stream function ____ to discard a portion of the input.

10 < x && x < 20

Which of the following expressions correctly determines that x is greater than 10 and less than 20?

==

Which of the following is a relational operator?

!=

Which of the following is the "not equal to" relational operator?

!

Which of the following operators has the highest precedence?

=

Which of the following operators has the lowest precedence?

if (x = 5)

Which of the following will cause a logical error if you are attempting to compare x to 5?

#define NDEBUG

You can disable assert statements by using which of the following?

True

You can use the function getline to read a string containing blanks. True or False

setfill

____ is a parameterized stream manipulator.