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If / Else Statements

Conditional statements let your program make decisions based on conditions.

Conditional Statements

Conditional statements execute different code depending on whether a condition is True or False.

if Statement

Executes a block only if the condition is True.

if-else Statement

Executes one block if True, another if False.

if-elif-else Chain

Test multiple conditions in sequence.

Nested if

An if statement inside another if statement.

Ternary Operator

One-line if-else: x if condition else y

Syntax

<pre><code># Basic if
score = 75
if score >= 60:
    print("Pass")

# if-else
if score >= 60:
    print("Pass")
else:
    print("Fail")

# if-elif-else
if score >= 90:
    grade = "A"
elif score >= 80:
    grade = "B"
elif score >= 70:
    grade = "C"
elif score >= 60:
    grade = "D"
else:
    grade = "F"
print(f"Grade: {grade}")

# Nested if
age = 20
has_id = True
if age >= 18:
    if has_id:
        print("Entry allowed")
    else:
        print("Need ID")

# Ternary (conditional expression)
status = "adult" if age >= 18 else "minor"
</code></pre>

Revision Notes

• if, elif, else — decision making
• Indentation defines the block
• elif = else if (no limit on elif)
• Ternary: value_if_true if condition else value_if_false
• Falsy: 0, "", None, [], {}, False

FizzBuzz

Easy

Print numbers from 1 to 100.
- For multiples of 3, print "Fizz"
- For multiples of 5, print "Buzz"
- For multiples of both, print "FizzBuzz"
- Otherwise print the number

Input:

N/A

Output:

1 2 Fizz 4 Buzz Fizz 7 8 Fizz Buzz

Show Hint

Use the modulus operator %. Check for both (3 and 5) first!

Solve this Challenge

Show Solution

for i in range(1, 101):
    if i % 15 == 0:
        print("FizzBuzz")
    elif i % 3 == 0:
        print("Fizz")
    elif i % 5 == 0:
        print("Buzz")
    else:
        print(i)

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