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Hey there! In this guide, we'll explore loops in Python. Loops are used to execute a block of code repeatedly based on a condition. Let's dive in!

Python Loops

  • Loops allow you to repeatedly execute a block of code while certain conditions are true.

  • Python provides two primary types of loops: for loops and while loops.

1. For Loop​

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

numbers = [1, 2, 3, 4, 5]             # List of numbers to iterate over  
for num in numbers: # Begin a 'for' loop over the 'numbers' list
print(num) # Print each number in the list

2. For Loop with Range​

You can also use the range() function to iterate over a sequence of numbers, especially when you want to loop for a specific number of times.

for i in range(1, 6):                 # Loop through numbers from 1 to 5 (range excludes 6)  
print(i) # Print each number in the range

3. While Loop​

The while loop in Python allows you to execute a block of code as long as a condition is true.

count = 1                             # Initialize a variable 'count' with value 1  
while count <= 5: # Continue looping while 'count' is less than or equal to 5
print(count) # Print the current value of 'count'
count += 1 # Increment 'count' by 1 in each iteration

4. Break Statement​

The break statement is used to exit a loop prematurely, even if the loop condition is still true.

for num in range(1, 11):              # Loop through numbers 1 to 10  
if num == 5: # Check if 'num' equals 5
break # Exit the loop when 'num' is 5
print(num) # Print numbers from 1 to 4

5. Continue Statement​

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

for num in range(1, 6):               # Loop through numbers from 1 to 5  
if num == 3: # Check if 'num' equals 3
continue # Skip the current iteration when 'num' is 3
print(num) # Print numbers except 3

6. Nested Loops​

In Python, you can use loops inside other loops. These are called nested loops and are useful for iterating over multi-dimensional data structures.

for i in range(1, 4):                 # Outer loop from 1 to 3  
for j in range(1, 3): # Inner loop from 1 to 2
print(f'Outer: {i}, Inner: {j}') # Print values of outer and inner loops

7. Loop Else Clause​

Python also provides an else clause that can be used with loops. The block under else is executed if the loop completes without hitting a break statement.

for num in range(1, 4):               # Loop through numbers from 1 to 3  
print(num) # Print the current value of 'num'
else: # Execute after the loop ends
print('Loop completed successfully.') # Print a success message