Day 11/100: Loop Control – break, continue, and pass

Welcome to Day 11 of the 100 Days of Python series!
Yesterday, we explored for loops and the range() function. Today, we’ll take things a step further and learn how to control the flow inside loops using three powerful tools: break, continue, and pass.

These commands let you:

• Stop a loop (break)
• Skip a specific iteration (continue)
• Use a placeholder for future code (pass)

Let’s break it down (pun intended). 🧠

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📦 What You’ll Learn

• What break, continue, and pass do in loops
• When to use each control statement
• Real-world examples of each
• Common pitfalls

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🛑 1. break — Stop the Loop Immediately

The break statement terminates the loop it's in — even if there are more iterations remaining.

🔸 Example:

for number in range(1, 10):
    if number == 5:
        break
    print(number)

Output:

1
2
3
4

As soon as number becomes 5, the loop breaks.

✅ Use break when:

• You want to exit a loop early
• You’ve found what you’re looking for

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⏭️ 2. continue — Skip to the Next Iteration

The continue statement skips the rest of the code inside the loop for the current iteration and jumps to the next iteration.

🔸 Example:

for number in range(1, 6):
    if number == 3:
        continue
    print(number)

Output:

1
2
4
5

When number == 3, Python skips the print().

✅ Use continue when:

• You want to skip certain values
• You want to avoid executing some code under specific conditions

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🚧 3. pass — Do Nothing (Placeholder)

The pass statement does nothing — literally. It’s used as a placeholder when you want to write syntactically correct code but haven't implemented it yet.

🔸 Example:

for number in range(1, 6):
    if number == 3:
        pass  # Do nothing (for now)
    print(number)

Output:

1
2
3
4
5

Unlike continue, pass does not skip the iteration — it just silently stands in place.

✅ Use pass when:

• You’re writing code ahead of time
• You need to define empty functions, classes, or blocks

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🔁 Combined Example

for number in range(1, 10):
    if number == 3:
        print("Skipping 3")
        continue
    elif number == 5:
        print("Breaking at 5")
        break
    elif number == 7:
        pass  # Placeholder — do nothing
    print(f"Number is: {number}")

Output:

Number is: 1
Number is: 2
Skipping 3
Number is: 4
Breaking at 5

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🧠 Real-World Use Cases

🔍 Searching for an Item

items = ["apple", "banana", "cherry", "grape"]

for item in items:
    if item == "cherry":
        print("Found cherry!")
        break

📋 Skipping Invalid Data

numbers = [5, 0, -3, 8, -1]

for num in numbers:
    if num < 0:
        continue
    print("Processing:", num)

🧪 Stubbing Future Code

def handle_user_input():
    # To be implemented later
    pass

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⚠️ Common Mistakes

• Using pass when you actually mean continue
• Forgetting to update loop variables in while loops (can cause infinite loops)
• Misplacing break, which might skip essential code

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🚀 Recap

Today you learned:

• ✅ break: exit a loop early
• ⏭️ continue: skip the rest of the current iteration
• 🚧 pass: placeholder that does nothing
• Real-life examples of loop control

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