DAY 001 : DATA TYPES IN PYTHON

📦 What is a Data Type?

A data type defines the kind of value a variable holds and what operations you can perform with it.

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🧮 Built-in Data Types in Python

🔢 Numbers

Type	Description	Example
int	Integer values	10, -3
float	Decimal values	3.14, -0.1
complex	Complex numbers (rare)	2 + 3j

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🔤 Text

Type	Description	Example
str	String - sequence of characters	"hello"

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✅ Boolean

Type	Description	Example
bool	Logical True or False	True, False

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📚 Sequence Types

Type	Description	Example
list	Ordered, changeable	[1, 2, 3]
tuple	Ordered, unchangeable	(4, 5, 6)
range	Sequence of numbers	range(5)

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🔑 Mapping Type

Type	Description	Example
dict	Key-value pairs	{"name": "Alice"}

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🪣 Set Types

Type	Description	Example
set	Unordered, unique items	{1, 2, 3}
frozenset	Immutable version of set	frozenset([1,2])

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🕳️ None Type

Type	Description	Example
NoneType	Represents no value / null	None

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🧪 How to Check a Variable's Data Type

x = 10
print(type(x))  # Output: <class 'int'>

float – Decimal Number

pi = 3.14
print(pi, type(pi))  # Output: 3.14 <class 'float'>

complex – Complex Number

z = 2 + 3j
print(z, type(z))  # Output: (2+3j) <class 'complex'>
🔤 Text Type
str – String (Text)

string:(Text)

name = "Alice"
print(name, type(name))  # Output: Alice <class 'str'>

✅ Boolean Type bool – True or False

is_active = True
print(is_active, type(is_active))  # Output: True <class 'bool'>

📚 Sequence Types list – Ordered, Changeable Collection

fruits = ["apple", "banana", "cherry"]
print(fruits, type(fruits))  # Output: ['apple', 'banana', 'cherry'] <class 'list'>
tuple – Ordered, Unchangeable Collection

colors = ("red", "green", "blue")
print(colors, type(colors))  # Output: ('red', 'green', 'blue') <class 'tuple'>
range – Sequence of Numbers

nums = range(5)
print(list(nums), type(nums))  # Output: [0, 1, 2, 3, 4] <class 'range'>

🔑 Mapping Type dict – Key-Value Pairs

person = {"name": "Alice", "age": 25}
print(person, type(person))  # Output: {'name': 'Alice', 'age': 25} <class 'dict'>

🪣 Set Types set – Unordered, Unique Items

unique_numbers = {1, 2, 3, 1}
print(unique_numbers, type(unique_numbers))  # Output: {1, 2, 3} <class 'set'>

frozenset – Immutable Set

frozen = frozenset([1, 2, 3])
print(frozen, type(frozen))  # Output: frozenset({1, 2, 3}) <class 'frozenset'>

🕳️ None Type NoneType – Represents No Value

empty = None
print(empty, type(empty))  # Output: None <class 'NoneType'>

📅 Day 2 – Variables, Operators, and Input/Output in Python

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✅ Variables

• Variables store data for later use.
• Syntax: variable_name = value

name = "Alice"// string variable
age = 25 // integer varible
height = 5.6// float variable

✅ Operators

In Python, operators are special symbols that perform operations on variables and values. They are the building blocks for performing calculations, comparisons, logical decisions, and more.

Types of Operators

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• arithmetic-operators
• comparison-operators
• assignment-operators
• logical-operators
• bitwise-operators
• membership operators
• identity-operators

Arithmetic operators

Used to perform mathematical operations.

a = 10
b = 3

print(a + b)   # 13 → Addition
print(a - b)   # 7  → Subtraction
print(a * b)   # 30 → Multiplication
print(a / b)   # 3.333... → Division
print(a // b)  # 3  → Floor Division
print(a % b)   # 1  → Modulus (remainder)
print(a ** b)  # 1000 → Exponent (power)

Comparison operators

Compare two values and return True or False.

x = 5
y = 10

print(x == y)  # False → Equal to
print(x != y)  # True  → Not equal to
print(x > y)   # False → Greater than
print(x < y)   # True  → Less than
print(x >= y)  # False → Greater than or equal to
print(x <= y)  # True  → Less than or equal to

Assignment Operators

Used to assign values and perform operations in one line.

x = 5
x += 2   # x = x + 2 → 7
x -= 1   # x = x - 1 → 6
x *= 3   # x = x * 3 → 18
x /= 2   # x = x / 2 → 9.0
x //= 2  # x = x // 2 → 4.0
x %= 3   # x = x % 3 → 1.0
x **= 2  # x = x ** 2 → 1.0
print(x)

Logical Operators

Used to combine conditional statements.

a = True
b = False

print(a and b)  # False → Both must be true
print(a or b)   # True  → At least one is true
print(not a)    # False → Inverts the value

Bitwise Operators

Operate on bits (binary values).

a = 5   # 0101
b = 3   # 0011

print(a & b)  # 1 → AND
print(a | b)  # 7 → OR
print(a ^ b)  # 6 → XOR
print(~a)     # -6 → NOT (inverts all bits)
print(a << 1) # 10 → Left shift
print(a >> 1) # 2  → Right shift

Membership Operators

Test if a value exists in a sequence (like string, list, tuple, etc).

name = "Python"

print("y" in name)     # True
print("z" not in name) # True

Identity Operators

Compare the memory location of two objects.

a = [1, 2, 3]
b = a
c = [1, 2, 3]

print(a is b)      # True  → Same object
print(a is c)      # False → Different objects
print(a is not c)  # True

Simple Program combining all operators

a = 10
b = 3

print(" Arithmetic Operators")
print("a + b =", a + b)   # 13
print("a - b =", a - b)   # 7
print("a * b =", a * b)   # 30
print("a / b =", a / b)   # 3.33...
print("a // b =", a // b) # 3
print("a % b =", a % b)   # 1
print("a ** b =", a ** b) # 1000
print()

#  Comparison Operators
print(" Comparison Operators")
print("a == b:", a == b)  # False
print("a != b:", a != b)  # True
print("a > b:", a > b)    # True
print("a < b:", a < b)    # False
print("a >= b:", a >= b)  # True
print("a <= b:", a <= b)  # False
print()

#  Assignment Operators
x = 5
print(" Assignment Operators")
x += 2   # x = x + 2
print("x += 2 →", x)
x *= 3   # x = x * 3
print("x *= 3 →", x)
print()

#  Logical Operators
is_sunny = True
have_umbrella = False
print(" Logical Operators")
print("is_sunny and have_umbrella:", is_sunny and have_umbrella)  # False
print("is_sunny or have_umbrella:", is_sunny or have_umbrella)    # True
print("not is_sunny:", not is_sunny)                               # False
print()

#  Bitwise Operators (just for demo)
print(" Bitwise Operators")
print("a & b =", a & b)   # 2
print("a | b =", a | b)   # 11
print()

#  Membership Operators
name = "Python"
print(" Membership Operators")
print("'y' in name:", 'y' in name)        # True
print("'a' not in name:", 'a' not in name) # True
print()

#  Identity Operators
list1 = [1, 2, 3]
list2 = list1
list3 = [1, 2, 3]
print(" Identity Operators")
print("list1 is list2:", list1 is list2)       # True
print("list1 is list3:", list1 is list3)       # False
print("list1 is not list3:", list1 is not list3) # True

Day 003: Python Lists 📝

Introduction

A list in Python is a collection of items in a particular order. Lists are mutable, meaning you can change their content after creation. They can hold items of different data types like numbers, strings, or even other lists.

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1. Creating a List

fruits = ["apple", "banana", "cherry"]
numbers = [1, 2, 3, 4, 5]
mixed = [1, "hello", 3.14, True]

2. Accessing List Items

fruits = ["apple", "banana", "cherry"] 
print(fruits[0])   # apple (first item)
print(fruits[-1])  # cherry (last item)

3. Changing List Items

fruits = ["apple", "banana", "cherry"]
fruits[1] = "blueberry"
print(fruits)  # ['apple', 'blueberry', 'cherry']

4. Adding Items to a List

fruits = ["apple", "banana", "cherry"]
fruits.append("orange")    # Add at the end
fruits.insert(1, "kiwi")   # Add at index 1
print(fruits)

append() and insert() keywords can be used to add element in list

5. Removing Items from a List

fruits = ["apple", "banana", "cherry"]
fruits.remove("apple")    # Remove by value
popped = fruits.pop()     # Remove last item
print(fruits)
print("Removed:", popped)

remove() and pop() keyword can be used to remove element from list

6. Looping Through a List

fruits = ["apple", "banana", "cherry"]
for fruit in fruits:
    print(fruit)

7. Joining Two Lists

fruits = ["apple", "banana", "cherry"]
vegetables = ["carrot", "lettuce"]
food = fruits + vegetables
print(food)

8. Sorting a List

numbers = [5, 2, 9, 1]
numbers.sort()        # Sort in ascending order
print(numbers)

numbers.sort(reverse=True)  # Sort descending
print(numbers)

sort() keyword is used for sorting elements on list

Summary Table

Operation	Method/Operator
Access	list[index]
Change	list[index] = value
Add (end)	list.append(value)
Add (any position)	list.insert(index, value)
Remove by value	list.remove(value)
Remove last item	list.pop()
Loop	for item in list:
Join	list1 + list2
Sort	list.sort()