Module 4

Question 1

While loop

Answer 1

Executes instructions repeatedly while a condition is true.

while CONDITION :
STATEMENTS

Question 2

count-controlled vs. event controlled

Answer 2

count controlled (aka definite) is used more-so as a counter and can be used a definite number of times, where as event controlled (indefinite) executes until an event occurs

Question 3

typical outline of a while loop

Answer 3

Update the loop variable

# Check the loop variable ( while ____ <= n)
# Update the loop variable ( VARIABLE +1)
# Print results

Question 4

When does a while loop not display an output?

Answer 4

When the loop is false, or when the loop runs forever

Question 5

What is an off-by-one error?

Answer 5

A common error when programming loops. Think through simple test cases to avoid this type of error.

Question 6

named argument

Answer 6

end= “”
by adding this as the last argument to the first print function, we indicate that an empty string is to be printed after the first argument is displayed. The output of the next print function starts on the same line where the previous one left off.

Example:

print(“00”, end=” “)
print(3+4)

output: 007

Question 7

sentinel value

Answer 7

denotes the end of a data set, but it is not part of the data

Question 8

priming read

Answer 8

the input operation before the loop, because it prepares or initializes the loop variable

Question 9

modification read

Answer 9

the input operation at the bottom of the loop is used to obtain the next input. It modifies the loop variable inside the loop.