Python Basics — break, continue, pass

break, continue, pass

These three keywords give you fine-grained control over loop execution — exit early, skip iterations, or leave a placeholder.

break — Exit the Loop

break immediately terminates the innermost loop:

for num in range(1, 10):
    if num == 5:
        print("Found 5! Stopping.")
        break
    print(num)

Output:

1
2
3
4
Found 5! Stopping.

Searching for an Item

names = ["Alice", "Bob", "Charlie", "Diana"]
target = "Charlie"

for name in names:
    if name == target:
        print(f"Found {target}!")
        break
else:
    print(f"{target} not found.")

Output:

Found Charlie!

Breaking from while

while True:
    command = input("Enter command (quit to exit): ")
    if command == "quit":
        break
    print(f"Running: {command}")

continue — Skip to Next Iteration

continue skips the rest of the current iteration and moves to the next one:

for num in range(1, 11):
    if num % 2 == 0:
        continue  # Skip even numbers
    print(num)

Output:

1
3
5
7
9

Filtering While Processing

scores = [85, -1, 92, 0, 78, -5, 95]

total = 0
count = 0

for score in scores:
    if score < 0:
        continue  # Skip invalid scores

    total += score
    count += 1

print(f"Average: {total / count:.1f}")  # Average: 62.5

pass — Do Nothing (Placeholder)

pass is a no-op statement. It does nothing but prevents a SyntaxError where Python expects a statement:

for i in range(5):
    pass  # TODO: implement later

Common Uses for pass

# Placeholder for a function
def process_data():
    pass  # Will implement later

# Placeholder for a class
class MyCustomError(Exception):
    pass

# Placeholder for a condition
if True:
    pass  # Nothing to do in this case

pass vs continue

# pass — does nothing, continues to next statement in body
for i in range(3):
    if i == 1:
        pass
    print(i)  # Prints 0, 1, 2

# continue — skips rest of body, goes to next iteration
for i in range(3):
    if i == 1:
        continue
    print(i)  # Prints 0, 2

Comparison Table

Keyword	Effect	Use Case
break	Exit the loop entirely	Found what you need, stop searching
continue	Skip to next iteration	Skip invalid data, filter during iteration
pass	Do nothing	Placeholder for future code

Loop-else Interaction with break

The else block of a for or while loop runs only when the loop exits normally (without break):

# break triggers — else does NOT run
for n in [2, 3, 4, 5, 6]:
    if n == 4:
        print("Found 4")
        break
else:
    print("4 not found")

Output:

Found 4

# No break — else runs
for n in [2, 3, 5, 6]:
    if n == 4:
        print("Found 4")
        break
else:
    print("4 not found")

Output:

4 not found

Prime Number Checker Using for-else

def is_prime(n):
    if n < 2:
        return False
    for i in range(2, int(n ** 0.5) + 1):
        if n % i == 0:
            return False  # Divisible — not prime
    return True

# Test
for num in range(2, 20):
    if is_prime(num):
        print(num, end=" ")

Output:

2 3 5 7 11 13 17 19

Practical Example: Input Validation with continue

entries = []

while len(entries) < 3:
    value = input(f"Enter number {len(entries) + 1} of 3: ")

    if not value.strip():
        print("  Empty input — skipped!")
        continue

    try:
        num = float(value)
    except ValueError:
        print(f"  '{value}' is not a number — skipped!")
        continue

    entries.append(num)

print(f"\nYour numbers: {entries}")
print(f"Average: {sum(entries) / len(entries):.2f}")

Summary

• break exits the loop immediately
• continue skips to the next iteration
• pass is a placeholder that does nothing
• break prevents the loop’s else from running
• continue does NOT affect else — only break does
• Use pass during development as a stub for unfinished code

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