Loops in Python

Loops in Python

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Definition of Loops:-

Loops means repeating something over and over until a particular condition is satisfied.

There are two types of Loops in Python:-

For Loop

1. for Loop in Python

Syntax:

for variable in range(start, stop, step):
    # code to be repeated

Explanation:

• for: Keyword to start the loop.
• variable: The name that will hold the current value of the loop at each iteration.
• in range(start, stop, step):
  • start: Where the loop starts (default is 0).
  • stop: The number the loop goes up to (but doesn't include).
  • step: How much to increase the variable after each loop (default is 1).

Example:

for i in range(0, 5):
    print(i)

• This will print numbers 0 to 4.

While Loop

2. while Loop in Python

Syntax:

while condition:
    # code to be repeated

Explanation:

• while: Keyword to start the loop.
• condition: This is a statement that is checked before each loop. If it’s True, the loop runs. If it’s False, the loop stops.
• The code inside the loop will keep repeating as long as the condition is True.

Example:

i = 0
while i < 5:
    print(i)
    i += 1

• This prints 0 to 4. The loop continues as long as i is less than 5.

Tips to Remember Python Loop Syntax:

1. for loop: Think of looping through a sequence. In Python, for is often used with range(), which creates a list of numbers.

   • Remember: for variable in range(start, stop):

2. while loop: Think of repeating something while a condition is true.

   • Remember: while condition:

Quick Tricks to Remember:

• Indentation: Python uses spaces (indentation) to define the block of code inside the loop. No curly braces {} like other languages.
• Colons (:): After the loop condition (whether for or while), always remember the colon :. This tells Python that the next lines are part of the loop.

Example to Remember Both Loops:

for loop:

for i in range(5):   # Repeat 5 times, from 0 to 4
    print(i)

while loop:

i = 0
while i < 5:   # Repeat as long as i is less than 5
    print(i)
    i += 1   # Increment i by 1

To summarize:

• for loop: Use it when you know how many times you want to repeat the loop (like counting).
• while loop: Use it when you want to repeat the loop as long as a condition is true.

Note:

Once you understand the logic behind each loop, remembering the syntax becomes easy. The key is practicing and writing loops frequently.