Chapter 5

Suppose sum and num are int variables, and the input is 18 25 61 6 -1. What is the output of the following code? sum = 0; cin >> num; while (num != -1) { sum = sum + num; cin >> num; } cout << sum << endl;

110

Suppose j, sum, and num are int variables, and the input is 26 34 61 4 -1. What is the output of the code? sum = 0; cin >> num; for (int j = 1; j <= 4; j++) { sum = sum + num; cin >> num; } cout << sum << endl;

125

Suppose sum, num, and j are int variables, and the input is 4 7 12 9 -1. What is the output of the following code? cin >> sum; cin >> num; for (j = 1; j <= 3; j++) { cin >> num; sum = sum + num; } cout << sum << endl;

24

What is the output of the following C++ code? count = 1; num = 25; while (count < 25) { num = num - 1; count++; } cout << count << " " << num << endl;

25 1

What is the next Fibonacci number in the following sequence? 1, 1, 2, 3, 5, 8, 13, 21, ...

34

What is the value of x after the following statements execute? int x = 5; int y = 30; do x = x * 2; while (x < y);

40

Consider the following code. (Assume that all variables are properly declared.) cin >> ch; while (cin) { cout << ch; cin >> ch; } This code is an example of a(n) ____ while loop.

EOF-controlled

Assume that all variables are properly declared. The following for loop executes 20 times. for (i = 0; i <= 20; i++) cout << i;

False

In a sentinel-controlled while loop, the body of the loop continues to execute until the EOF symbol is read.

False

The following while loop terminates when j > 20. j = 0; while (j < 20) j++;

False

The statement in the body of a while loop acts as a decision maker.

False

Assume all variables are properly declared. The output of the following C++ code is 2 3 4 5. n = 1; while (n < 5) { n++; cout << n << " "; }

True

In a counter-controlled while loop, the loop control variable must be initialized before the loop.

True

In the case of the sentinel-controlled while loop, the first item is read before the while loop is entered.

True

The control statements in the for loop include the initial statement, loop condition, and update statement.

True

____ loops are called posttest loops.

do...while

Which of the following loops is guaranteed to execute at least once?

do...while loop

A(n) ____-controlled while loop uses a bool variable to control the loop.

flag

When a continue statement is executed in a ____, the update statement always executes.

for loop

What is the initial statement in the following for loop? (Assume that all variables are properly declared.) int i; for (i = 1; i < 20; i++) cout << "Hello World"; cout << "!" << endl;

i = 1;

A loop that continues to execute endlessly is called a(n) ____ loop.

infinite

What executes immediately after a continue statement in a while and do-while loop?

loop-continue test

In ____ structures, the computer repeats particular statements a certain number of times depending on some condition(s).

looping

What is the output of the following C++ code? int j; for (j = 10; j <= 10; j++) cout << j << " "; cout << j << endl;

10 11

What is the output of the following C++ code? num = 10; while (num > 10) num = num - 2; cout << num << endl;

10

The control variable in a flag-controlled while loop is a bool variable.

True

The number of iterations of a counter-controlled loop is known in advance.

True

The ____ statement can be used to eliminate the use of certain (flag) variables.

break

Consider the following code. int limit; int reps = 0; cin >> limit; while (reps < limit) { cin >> entry; triple = entry * 3; cout << triple; reps++; } cout << endl; This code is an example of a(n) ____ while loop.

counter-controlled

Which of the following is a repetition structure in C++?

do...while

Which of the following statements generates a random number between 0 and 50?

srand(time(0)); num = rand() % 50;

Which executes first in a do...while loop?

the statement