Day 4 of the Ultimate Learning Challenge : Mastering the Basics of Python

Hellooo, welcome back to day 4 of mastering the basics of Python. Today, In this blog we’ll take a look at Lists and Tuples in Python.

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Python Lists

In Python, lists are one of the most commonly used and versatile built-in data structures. They allow you to store multiple items in a single variable, and these items can be of any data type—strings, integers, floats, even other lists. List are

• Ordered

• Mutable

• Iterable collection of elements.

Syntax:

pythonCopyEditmy_list = [1, 2, 3, 4, 5]

You can also create an empty list like this:

pythonCopyEditempty_list = []

Or using the list() constructor:

pythonCopyEditanother_empty_list = list()

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Accessing List Elements

Use indexing to access individual elements. Index starts at 0.

pythonCopyEditfruits = ['apple', 'banana', 'cherry']
print(fruits[0])  # apple

You can also use negative indexing:

pythonCopyEditprint(fruits[-1])  # cherry

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Slicing Lists

You can extract sublists using slicing:

pythonCopyEditnumbers = [10, 20, 30, 40, 50]
print(numbers[1:4])  # [20, 30, 40]
print(numbers[:3])   # [10, 20, 30]
print(numbers[::2])  # [10, 30, 50]

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Modifying Lists

Changing elements:

pythonCopyEditmy_list = [1, 2, 3]
my_list[1] = 20
print(my_list)  # [1, 20, 3]

Adding elements:

pythonCopyEditmy_list.append(4)      # Adds to end
my_list.insert(1, 100) # Inserts at index 1

Removing elements:

pythonCopyEditmy_list.remove(100)    # Removes by value
my_list.pop()          # Removes last item
del my_list[0]         # Removes by index

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Common List Methods

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Looping Through Lists

Using a for loop:

pythonCopyEditfor fruit in fruits:
    print(fruit)

Using enumerate():

pythonCopyEditfor index, value in enumerate(fruits):
    print(index, value)

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List Comprehensions

Create new lists in a clean and efficient way:

pythonCopyEditsquares = [x**2 for x in range(5)]  # [0, 1, 4, 9, 16]

With condition:

pythonCopyEditevens = [x for x in range(10) if x % 2 == 0]

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Nesting Lists

Lists can contain other lists:

pythonCopyEditmatrix = [[1, 2], [3, 4], [5, 6]]
print(matrix[1][0])  # 3

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Copying Lists

Using = copies the reference, not the list:

pythonCopyEdita = [1, 2, 3]
b = a
b[0] = 100
print(a)  # [100, 2, 3]

Use .copy() or list() to avoid this:

pythonCopyEditc = a.copy()
c[0] = 999
print(a)  # [100, 2, 3]
print(c)  # [999, 2, 3]

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Built-in Functions with Lists

pythonCopyEditlen(my_list)     # Number of elements
sum(my_list)     # Sum of all numeric elements
min(my_list)     # Smallest value
max(my_list)     # Largest value
sorted(my_list)  # Returns a new sorted list

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Python Tuples

Tuples are used to store multiple items in a single variable. A tuple is a collection which is ordered and unchangeable. Tuples are written with round brackets. Tuples are

• Ordered

• Immutable

• Allow duplicates

Syntax:

my_tuple = (1, 2, 3)

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Tuple Properties

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Creating Tuples

# Empty tuple
t1 = ()

# Tuple with integers
t2 = (1, 2, 3)

# Mixed data types
t3 = ("Python", 3.14, True)

# Single-element tuple (don’t forget the comma!)
t4 = (42,)

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Accessing Tuple Elements

You can use indexing:

t = ("Mango", "Apple", "Cherry")
print(t[0])   # Mango
print(t[-1])  # Cherry

Slicing:

print(t[0:2])  # ('Mango', 'Apple')

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Basic Operations on Tuples

Concatenate using +

a = (1, 2)
b = (3, 4)
print(a + b)  # (1, 2, 3, 4)

Repeat using *

t = ("Python",)
print(t * 3)  # ('Python', 'Python', 'Python')

Check Membership using in

t = (1, 2, 3)
print(2 in t)  # True
print(5 in t)  # False

Find Length using len()

t = ("a", "b", "c")
print(len(t))  # 3

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Nested Tuples

Tuples can contain other tuples:

nested = ((1, 2), (3, 4), (5, 6))

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Accessing Elements in Nested Tuples

nested = ((1, 2), (3, 4), (5, 6))
print(nested[1])      # (3, 4)
print(nested[1][0])   # 3

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Immutable Tuples

You cannot change a tuple after it's created:

t = (1, 2, 3)
t[0] = 100  # Error: 'tuple' object does not support item assignment

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Inserting Elements in a Tuple

Tuples do not support direct insertion. You can convert to a list, insert, then convert back:

t = (1, 2, 3)
temp = list(t)
temp.insert(1, 100)
t = tuple(temp)
print(t)  # (1, 100, 2, 3)

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Modifying Elements of a Tuple

Same approach — convert to a list:

t = (1, 2, 3)
temp = list(t)
temp[0] = 42
t = tuple(temp)
print(t)  # (42, 2, 3)

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Deleting Elements from a Tuple

You cannot delete individual elements, but you can delete the entire tuple:

t = (1, 2, 3)
del t

To "remove" an element, use list conversion:

t = (1, 2, 3)
temp = list(t)
temp.remove(2)
t = tuple(temp)
print(t)  # (1, 3)

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:> To be Continued…

Happy Learning !

Thanks for reading :)