CS 150 Chapter 5
posttest
A do...while loop is a(n) ____________________ loop, since the loop condition is evaluated after executing the body of the loop.
indexed
A for loop is typically called a counted or ____________________ for loop.
invariant
A loop ____________________ is a set of statements that remains true each time the loop body is executed.
infinite
A loop that continues to execute endlessly is called a(n) ____ loop.
semantic
A semicolon at the end of the for statement (just before the body of the loop) is a(n) ____________________ error.
patch
A software ____________________ is a piece of code written on top of an existing piece of code intended to fix a bug in the original code.
flag
A(n) ____-controlled while loop uses a bool variable to control the loop.
counter-controlled
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.
EOF-controlled
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.
In a sentinel-controlled while loop, the body of the loop continues to execute until the EOF symbol is read.
F
The statement in the body of a while loop acts as a decision maker.
False
continue
If a(n) ____________________ statement is placed in a do...while structure, the loop-continue test is evaluated immediately after this statement.
looping
In ____ structures, the computer repeats particular statements a certain number of times depending on some condition(s).
pretest
In a while and for loop, the loop condition is evaluated before executing the body of the loop. Therefore, while and for loops are called ____________________ loops.
off-by-one or off-by-1 or off by one or off by 1
In a(n) "____________________" problem, either the loop executes one too many or one too few times.
nesting or nested
Putting one control structure statement inside another is called ____________________.
125
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;
110
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;
24
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;
In a counter-controlled while loop, the loop control variable must be initialized before the loop.
T
The number of iterations of a counter-controlled loop is known in advance.
T
break
The ____ statement can be used to eliminate the use of certain (flag) variables.
do...while or do while or do/while or do-while
The ____________________ loop has an exit condition but no entry condition.
break
The ____________________ statement is typically used for two purposes:
True
The control statements in the for loop include the initial statement, loop condition, and update statement.
istream
The function eof is a member of the data type ____________________.
unsigned
The function srand takes as input a(n) ____________________ int, which acts as the seed for the algorithm.
cstdlib
To generate a random number, you can use the function rand of the header file ____________________.
loop-continue test
What executes immediately after a continue statement in a while and do-while loop?
i = 1;
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;
34
What is the next Fibonacci number in the following sequence? 1, 1, 2, 3, 5, 8, 13, 21, ...
25 1
What is the output of the following C++ code? count = 1; num = 25; while (count < 25) { num = num - 1; count++; } cout << count << " " << num << endl;
10 11
What is the output of the following C++ code? int j; for (j = 10; j <= 10; j++) cout << j << " "; cout << j << endl;
155
What is the output of the following C++ code? num = 100; while (num <= 150) num = num + 5; cout << num << endl;
10
What is the output of the following C++ code? num = 10; while (num > 10) num = num - 2; cout << num << endl;
This is an infinite loop.
What is the output of the following loop? count = 5; cout << 'St'; do { cout << 'o'; count--; } while (count <= 5);
40
What is the value of x after the following statements execute? int x = 5; int y = 30; do x = x * 2; while (x < y);
for loop
When a continue statement is executed in a ____, the update statement always executes.
the staement
Which executes first in a do...while loop?
do...while
Which of the following is a repetition structure in C++?
do...while loop
Which of the following loops does not have an entry condition?
do...while loop
Which of the following loops is guaranteed to execute at least once?
srand(time(0)); num = rand() % 50;
Which of the following statements generates a random number between 0 and 50?
do...while
____ loops are called posttest loops.