Loops in Python

Loops in Python are used to execute a block of code repeatedly as long as a certain condition is met. Python provides two main types of loops: for and while loops.

1. for Loop

The for loop is used to iterate over a sequence (such as a list, tuple, dictionary, or string) and execute a block of code for each element.

numbers = [1, 2, 3, 4, 5]
for num in numbers:
    print(num)

Using range() with for Loop

The range() function generates a sequence of numbers.

for i in range(5):  # Iterates from 0 to 4
    print("Iteration:", i)

2. while Loop

The while loop executes a block of code as long as the given condition is True.

count = 0
while count < 5:
    print("Count:", count)
    count += 1

3. Nested Loops

A loop inside another loop is called a nested loop.

for i in range(3):
    for j in range(2):
        print(f"i: {i}, j: {j}")

4. Loop Control Statements

Python provides loop control statements to modify the flow of loops:

break Statement

The break statement stops the loop prematurely when a condition is met.

for num in range(10):
    if num == 5:
        break  # Stops the loop when num is 5
    print(num)

continue Statement

The continue statement skips the current iteration and moves to the next.

for num in range(5):
    if num == 2:
        continue  # Skips when num is 2
    print(num)

pass Statement

The pass statement is a placeholder that does nothing.

for i in range(3):
    pass  # Placeholder for future code

Conclusion

Loops are essential for automation and iterative processing in Python. Understanding their behavior helps in writing efficient and effective code.