Python Lists

A list in Python is a collection of items that are ordered, changeable (mutable), and allow duplicate values. Lists are written with square brackets [].

Python में list एक ऐसा collection है जिसमें items ordered होते हैं, उन्हें बदला जा सकता है (mutable होते हैं), और duplicate values भी हो सकती हैं। इसे [] में लिखा जाता है।

Why and When to Use Lists?

• Store multiple values in a single variable
• Good for collections like student names, marks, etc.
• Can easily loop through and modify elements

• एक ही variable में कई values रखने के लिए
• जैसे student के नाम या marks को list में store कर सकते हैं
• Elements को loop और modify करना आसान होता है

Basic Example

Copyfruits = ["apple", "banana", "cherry"]
print(fruits)

["apple", "banana", "cherry"]

Useful List Functions in Python

1. append(): Add item to end

   Copyfruits = ["apple", "banana", "cherry"]
   fruits.append("orange")
   print(fruits)

   Output:

   ["apple", "banana", "cherry", "orange"]

2. insert(): Add at specific index

   Copyfruits = ["apple", "banana", "cherry"]
   fruits.insert(1, "grape")
   print(fruits)

   Output:

   ["apple", "grape", "banana", "cherry"]

3. remove(): Remove specific item

   Copyfruits = ["apple", "banana", "cherry"]
   fruits.remove("banana")
   print(fruits)

   Output:

   ["apple", "cherry"]

4. pop(): Remove last item (or by index)

   Copyfruits = ["apple", "banana", "cherry"]
   fruits.pop()
   print(fruits)

   Output:

   ["apple", "banana"]

5. sort(): Sort list alphabetically or numerically

   Copyfruits = ["banana", "apple", "cherry"]
   fruits.sort()
   print(fruits)

   Output:

   ["apple", "banana", "cherry"]

6. reverse(): Reverse list order

   Copyfruits = ["apple", "banana", "cherry"]
   fruits.reverse()
   print(fruits)

   Output:

   ["cherry", "banana", "apple"]

7. len(): Get number of items

   Copyfruits = ["apple", "banana", "cherry"]
   print(len(fruits))

   Output:

   3