Chapter 5, Problem 1MC

A ______ controlled loop uses a true/false condition to control the number of times that it repeats.

1. a. Boolean
2. b. condition
3. c. decision
4. d. count

Program Description Answer

The “while” loop is a condition controlled loop, it controls the number of times that repeats.

Hence, the correct answer is option “B”.

Explanation of Solution

Condition controlled loop:

This is a loop which exhibits true or false condition to control the number of times that the loop repeats. For example: “while” loop is a condition controlled loop.

• The “while” loop first checks its expression and then, the statements inside the loop gets executed. It is also called as pretest loops.
• The loop gets terminated when the condition becomes false.

Syntax:

Syntax for the “while” loop is as follows:

while boolean_expression:

# while suite

Example Program:

Consider the following example of condition controlled loop:

#initialization of variable

a=1

#execute the while loop until a is less than or equal to 5

while a<=5:

    #Print the value of a

    print(a)

    #Increment a by 1 for each iteration of loop

    a+=1

Explanation:

In the above code, the “while” loop executes until the value of “a” is less than or equal to 5 and then it exits from the program when the condition inside the loop gets failed.

Explanation of incorrect options:

Boolean:

Boolean is not a loop instead it is a data type which is represented with two values either true or false. This value is based upon the flow of the action performed by the program.

Hence, the option “A” is wrong.

Decision:

A decision is not a loop and it decides the case to be executed based upon the situation.

Hence, the option “C” is wrong.

Count:

This is a loop which repeats specific number of times and it keeps track of the counter variable to keeps track about the number of times that the loop executes. For example: “for” loop is a counter controlled loop.

Hence, the option “D” is wrong.

Sample Output

1

2

3

4

5