3.6 Conditionals

POPCORN HACK 1

Code Runner Challenge

POPCORN HACK 1

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# CODE_RUNNER: POPCORN HACK 1

amount_requested = 0

# 1 condition -> 2 outcomes -> 2 answers
if amount_requested > 100:
    print("This message is asking for a large amount of money.")
else:
    print("This message is asking for a small amount of money.")

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Lines: 1 Characters: 0

Output

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POPCORN HACK 2

Code Runner Challenge

POPCORN HACK 2

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# CODE_RUNNER: POPCORN HACK 2

risk_score = 9

# Broken version with risk_score >= 3 first prints the mild warning for 9.
# Unreachable in the broken version: risk_score >= 6 and risk_score >= 9.
# Fixed order: 9, 6, 3, else.
if risk_score >= 9:
    print("Do not reply. This is almost certainly a scam.")
elif risk_score >= 6:
    print("This looks risky. Check with someone you trust before replying.")
elif risk_score >= 3:
    print("Be a little careful, but this is probably fine.")
else:
    print("Nothing suspicious in this message.")

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Lines: 1 Characters: 0

Output

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HOMEWORK HACK

Code Runner Challenge

HOMEWORK HACK

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# CODE_RUNNER: HOMEWORK HACK

message = "URGENT: send gift cards now to unlock your account"
amount_requested = 500
known_contact = False

risk_score = 0

# Add to risk_score using conditionals, one signal at a time.
# Each if is independent because a message can trigger multiple signals at once.
# No else is needed, because we want to keep adding points for each matching signal.
if "gift card" in message:
    risk_score += 4
if amount_requested > 100:
    risk_score += 3
if not known_contact:
    risk_score += 2

# 4 thresholds -> 5 outcomes -> 5 answers
if risk_score >= 9:
    print("Do not reply. This is almost certainly a scam.")
elif risk_score >= 6:
    print("This looks risky. Check with someone you trust before replying.")
elif risk_score >= 3:
    print("Be a little careful, but this is probably fine.")
elif risk_score >= 1:
    print("A little suspicious. Keep an eye on it.")
else:
    print("Nothing suspicious in this message.")

print(f"Final risk score: {risk_score}")

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Lines: 1 Characters: 0

Output

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Reachability proof

Extreme Tests

Code Runner Challenge

TEST

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# CODE_RUNNER: TEST

message = "Hi Mom, are we still on for Sunday?"
amount_requested = 0
known_contact = True

risk_score = 0

# Each if is an independent signal, so false signals simply add 0.
if "gift card" in message:
    risk_score += 4
if amount_requested > 100:
    risk_score += 3
if not known_contact:
    risk_score += 2

# 4 thresholds -> 5 outcomes -> 5 answers
if risk_score >= 9:
    print("Do not reply. This is almost certainly a scam.")
elif risk_score >= 6:
    print("This looks risky. Check with someone you trust before replying.")
elif risk_score >= 3:
    print("Be a little careful, but this is probably fine.")
elif risk_score >= 1:
    print("A little suspicious. Keep an eye on it.")
else:
    print("Nothing suspicious in this message.")

print(f"Final risk score: {risk_score}")

Python Java JavaScript Pseudocode 14px 16px 18px 20px

Lines: 1 Characters: 0

Output

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Code Runner Challenge

TEST

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# CODE_RUNNER: TEST

message = "URGENT: send gift cards now to unlock your account"
amount_requested = 500
known_contact = False

risk_score = 0

# Each if is an independent signal, so true signals can stack together.
if "gift card" in message:
    risk_score += 4
if amount_requested > 100:
    risk_score += 3
if not known_contact:
    risk_score += 2

# 4 thresholds -> 5 outcomes -> 5 answers
if risk_score >= 9:
    print("Do not reply. This is almost certainly a scam.")
elif risk_score >= 6:
    print("This looks risky. Check with someone you trust before replying.")
elif risk_score >= 3:
    print("Be a little careful, but this is probably fine.")
elif risk_score >= 1:
    print("A little suspicious. Keep an eye on it.")
else:
    print("Nothing suspicious in this message.")

print(f"Final risk score: {risk_score}")

Python Java JavaScript Pseudocode 14px 16px 18px 20px

Lines: 1 Characters: 0

Output

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