实用指南：【ATBS with Python】QA Chap2 If-else and Flow Control

Automate The Boring Stuff with Python

Practice Questions

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文章目录

• Automate The Boring Stuff with Python
• • Chap2 If-else and Flow Control

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Chap2 If-else and Flow Control

1. What are the two values of the Boolean data type? How do you write them?

True and False

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2. What are the three Boolean operators?
   and, or ,not

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3. Write out the truth tables of each Boolean operator (that is, every possible combination of Boolean values for the operator and what they evaluate to).

and	True and True	True
	True and False	False
	False and True	False
	False and False	False
or	True or True	True
	True or False	True
	False or True	True
	False and False	False
not	not True	False
	not False	True

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4. What do the following expressions evaluate to?

(5 > 4) and (3 == 5) : False
not (5 > 4) : False
(5 > 4) or (3 == 5) : True
not ((5 > 4) or (3 == 5)) : False
(True and True) and (True == False) : False
(not False) or (not True) :True

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5. What are the six comparison operators?
   ==, !=, <, >, <=, >=

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6. What is the difference between the equal to operator and the assignment operator?

The equal to operator asks whether two values are the same as each other.

The assignment operator puts the value on the right into the variable on the left

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7. Explain what a condition is and where you would use one.

A condition is a statement or expression that evaluates to either true or false, often used to control the flow of a program. Conditions are commonly used in if statements, loops, and switch cases to determine which code should run based on specific criteria.

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8. Identify the three blocks in this code:

spam = 0
if spam == 10:
print('eggs')
if spam > 5:
print('bacon')
else:
print('ham')
print('spam')
print('Done')

• Block 1: Outer if Statement

if spam == 10:
print('eggs')
if spam > 5:
print('bacon')
else:
print('ham')
print('spam')

This is the outermost block, controlled by the condition spam == 10. It includes all indented lines beneath it.

• Block 2: Inner if-else Statement

if spam > 5:
print('bacon')
else:
print('ham')

Nested within the first block, this if-else structure checks the condition spam > 5. The indented lines under each clause form sub-blocks within this block.

• Block 3: Unconditional print Statement

print('Done')

This line is outside all conditional blocks and executes regardless of the conditions above. It is not indented, marking it as separate from the other blocks.

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9. Write code that prints Hello if 1 is stored in spam, prints Howdy if 2 is stored in spam, and prints Greetings! if anything else is stored in spam.

if spam == 1:
print('Hello')
elif spam == 2:
print('Howdy')
else: print('Greetings!')