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For Loop with else in Python

 

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For Loop with Else in Python

In Python, a `for` loop can have an `else` clause that executes when the loop completes normally (i.e., not interrupted by a `break` statement). Here are some examples:

1. Basic Example

In this example, the `else` block executes because the loop completes without encountering a `break` statement.


# A list of numbers
numbers = [1, 2, 3, 4, 5]

# Iterate through the list
for number in numbers:
    print(number)
else:
    print("Loop completed without break")

# Output:
# 1
# 2
# 3
# 4
# 5
# Loop completed without break

2. With Break

In this example, the `else` block does not execute because the loop is terminated by a `break` statement.


# A list of numbers
numbers = [1, 2, 3, 4, 5]

# Iterate through the list
for number in numbers:
    if number == 3:
        break
    print(number)
else:
    print("Loop completed without break")

# Output:
# 1
# 2

3. Searching in a List

Using `else` with a `for` loop can be helpful for search operations where you need to know if an item was found or not.


# A list of fruits
fruits = ['apple', 'banana', 'cherry']

# Item to search for
search_item = 'banana'

# Iterate through the list
for fruit in fruits:
    if fruit == search_item:
        print(fruit, "found!")
        break
else:
    print(search_item, "not found!")

# Output:
# banana found!

4. No Break

When the item is not found, the `else` block executes because the loop completes normally.


# A list of fruits
fruits = ['apple', 'banana', 'cherry']

# Item to search for
search_item = 'orange'

# Iterate through the list
for fruit in fruits:
    if fruit == search_item:
        print(fruit, "found!")
        break
else:
    print(search_item, "not found!")

# Output:
# orange not found!
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