Python Programming - Loops

The else block in a for loop in Python has a specific behavior: it only executes when the loop completes all its iterations without encountering a break statement.

If a break statement is used to prematurely terminate the loop, the else block is skipped. This is because the break statement interrupts the normal flow of the loop, preventing it from reaching the end.

# Example
for number in range(10):
    if number == 5:
        break
    print(number)
else:
    print("The loop completed normally.")

In this example, the loop iterates from 0 to 9. When number reaches 5, the break statement is executed, and the loop terminates early. As a result, the else block is not executed.

The reversed() function is used to iterate over a list in reverse order in Python.

while True: creates an infinite loop, as the condition is always true.

The break statement is used to exit a loop prematurely, regardless of the loop's condition. Here's an example of using the break statement in a loop:

for i in range(1, 6):
    if i == 3:
        break
    print(i)

In this example, when the value of i becomes 3, the break statement is executed, causing the loop to terminate prematurely. As a result, only the numbers 1 and 2 are printed before the loop is exited.

The for loop in Python is commonly used for iterating over a sequence of numbers with a specified step size.

for i in range(0, 10, 2):  # start at 0, stop before 10, step size of 2
    print(i)

In this example, the for loop iterates over the sequence of numbers from 0 to 8 (10 is not included) with a step size of 2, and prints each number to the console.