Nested If Statements
You can have if statements inside if statements. This is called nested if statements.
Example
x = 41
if x > 10:
print("Above ten,")
if x > 20:
print("and also above 20!")
else:
print("but not above 20.")
In this example, the inner if statement only runs if the outer condition (x > 10) is true.
How Nested If Works
Each level of nesting creates a deeper level of decision-making. The code evaluates from the outermost condition inward.
Example
age = 25
has_license = True
if age >= 18:
if has_license:
print("You can drive")
else:
print("You need a license")
else:
print("You are too young to drive")
Multiple Levels of Nesting
You can nest as many levels deep as needed, but keep in mind that too many levels can make code harder to read.
Example
score = 85
attendance = 90
submitted = True
if score >= 60:
if attendance >= 80:
if submitted:
print("Pass with good standing")
else:
print("Pass but missing assignment")
else:
print("Pass but low attendance")
else:
print("Fail")
Nested If vs Logical Operators
Sometimes nested if statements can be simplified using logical operators like and. The choice depends on your logic.
Example
temperature = 25
is_sunny = True
if temperature > 20:
if is_sunny:
print("Perfect beach weather!")
Example
temperature = 25
is_sunny = True
if temperature > 20 and is_sunny:
print("Perfect beach weather!")
Both approaches produce the same result. Use nested if statements when the inner logic is complex or depends on the outer condition. Use and when both conditions are simple and equally important.
More Examples
Example
username = "Emil"
password = "python123"
is_active = True
if username:
if password:
if is_active:
print("Login successful")
else:
print("Account is not active")
else:
print("Password required")
else:
print("Username required")
Example
score = 92
extra_credit = 5
if score >= 90:
if extra_credit > 0:
print("A+ grade")
else:
print("A grade")
elif score >= 80:
print("B grade")
else:
print("C grade or below")
