Python Lesson 7: Operators

Operators are symbols that perform operations on values. You will use them constantly in every Python program.

Arithmetic Operators

a = 10
b = 3

print(a + b)   # 13  — addition
print(a - b)   # 7   — subtraction
print(a * b)   # 30  — multiplication
print(a / b)   # 3.333... — division (always float)
print(a // b)  # 3   — floor division (whole number only)
print(a % b)   # 1   — modulo (remainder)
print(a ** b)  # 1000 — exponentiation (10 to the power 3)

Comparison Operators (return True or False)

x = 5
y = 10

print(x == y)   # False — equal
print(x != y)   # True  — not equal
print(x < y)    # True  — less than
print(x > y)    # False — greater than
print(x <= 5)   # True  — less than or equal
print(x >= 10)  # False — greater than or equal

Logical Operators

age = 20
has_id = True

# and — both conditions must be True
print(age >= 18 and has_id)   # True

# or — at least one must be True
print(age < 18 or has_id)     # True

# not — reverses True/False
print(not has_id)              # False

Assignment Shortcuts

score = 100
score += 10   # score = score + 10  -> 110
score -= 5    # score = score - 5   -> 105
score *= 2    # score = score * 2   -> 210
score //= 3   # score = score // 3  -> 70
print(score)  # 70