And, Or, Not, randint

CSD1010: Week 2B

Wiedemann • Fall 2025

Logical Operator: and

• Evaluates to True only if both sides are True.

A	B	A and B
True	True	True
True	False	False
False	True	False
False	False	False

if temperature > 70 and is_sunny:
    print("Perfect beach weather!")

Logical Operator: or

• Evaluates to True if either side is True.

A	B	A or B
True	True	True
True	False	True
False	True	True
False	False	False

if is_weekend or is_holiday:
    print("No school today!")

Logical Operator: not

• Flips the truth value of a boolean expression.
• not True becomes False.
• not False becomes True.

A	not A
True	False
False	True

if not is_raining:
    print("Good day for a walk")

Operator Precedence

• Python checks not first, then and, then or when evaluating compound conditionals.
• In any case, it is safest to use parentheses to make your intentions clear.

# Without parentheses: is this right? (No.)
can_go = has_ticket or has_pass and not is_full

# With parentheses: less error-prone, clearer meaning
can_go = (has_ticket or has_pass) and not is_full

Random Integers

• The random module provides various functions for generating randomness.
• random.randint(a, b) returns a random integer between a and b (inclusive).

import random

# Simulate a dice roll
roll = random.randint(1, 6)
print(f"You rolled a {roll}")