# Example 1: Creating variables
student_name = "Gurpreet Singh"
age = 17
course_fee = 0.0  # Free course at Brilliant P

print(student_name)
print(age)

# Example 2: Multiple assignments in one line
x, y, z = 10, 20, 30
print(x, y, z)

# Example 3: Assigning same value to multiple variables
a = b = c = 100
print(a, b, c)

# Example 4: Updating variable value
score = 50
score = score + 10
print("Updated Score:", score)

# 1. Integer (int) - Whole positive or negative numbers
students_count = 250

# 2. Float (float) - Numbers with decimal points
percentage = 95.8

# 3. String (str) - Sequence of characters enclosed in quotes
school_name = "Brilliant P Academy"

# 4. Boolean (bool) - True or False (Case-sensitive!)
is_course_free = True

# Using type() function to inspect data type
print(type(students_count))  # Output: <class 'int'>
print(type(percentage))      # Output: <class 'float'>
print(type(school_name))      # Output: <class 'str'>
print(type(is_course_free))  # Output: <class 'bool'>

# Type Conversion (Casting)
num_str = "50"
num_int = int(num_str)  # Converts String "50" to Integer 50
print(num_int + 10)    # Result: 60

# 1. Arithmetic Operators (+, -, *, /, %, //, **)
a = 17
b = 5

print("Addition:", a + b)        # 22
print("Division:", a / b)        # 3.4 (Returns float)
print("Floor Division:", a // b)  # 3 (Removes decimal)
print("Modulus (Remainder):", a % b) # 2
print("Exponent (Power):", b ** 3) # 5^3 = 125

# 2. Comparison Operators (==, !=, >, <, >=, <=)
print("Is a equal to b?", a == b)    # False
print("Is a greater than b?", a > b) # True

# 3. Logical Operators (and, or, not)
has_passed = True
has_fee_paid = True

print("Eligible for Certificate?", has_passed and has_fee_paid) # True

# 4. Membership Operators (in, not in)
course_name = "Python Masterclass"
print("'Py' in course?", "Py" in course_name) # True

# Example 1: Simple if-else statement
age = 18

if age >= 18:
    print("You are eligible to vote!")
else:
    print("You are not eligible yet.")

# Example 2: Grade Evaluation using if-elif-else
marks = 85

if marks >= 90:
    grade = "A+"
elif marks >= 80:
    grade = "A"
elif marks >= 70:
    grade = "B"
else:
    grade = "C"

print("Your Grade is:", grade)

# Example 3: Short-hand Ternary Operator
status = "Adult" if age >= 18 else "Minor"
print("Status:", status)

# 1. for loop with range(start, stop, step)
print("Counting 1 to 5:")
for i in range(1, 6):
    print("Number:", i)

# 2. while loop - repeats while condition is True
count = 3
while count > 0:
    print("Countdown:", count)
    count -= 1

# 3. break statement - exits loop immediately
for num in range(1, 10):
    if num == 4:
        break
    print("Loop item:", num)

# 4. continue statement - skips current iteration
for x in range(1, 5):
    if x == 3:
        continue  # Skips 3
    print("Value:", x)

# 1. Defining a function with parameters
def greet_student(name, course="Python"):
    """This function greets a student."""
    return f"Hello {name}, welcome to {course} at Brilliant P!"

# Calling the function
message1 = greet_student("Amritpal")
message2 = greet_student("Gurnain", "Web Dev")

print(message1)
print(message2)

# 2. Function returning calculated result
def calculate_total(price, tax_rate):
    total = price + (price * tax_rate)
    return total

bill = calculate_total(500, 0.18)
print("Total Bill:", bill)

# 3. Anonymous Lambda Function (One-line function)
square = lambda x: x * x
print("Square of 6:", square(6))

# 1. Creating a list
courses = ["Python", "Calligraphy", "Canva", "Web Dev"]

# 2. Accessing elements using zero-based indexing
print("First course:", courses[0])   # Python
print("Last course:", courses[-1])   # Web Dev (Negative index)

# 3. List Slicing [start : stop]
print("First 2 courses:", courses[0:2])

# 4. Adding elements: append(), insert()
courses.append("Video Editing")       # Adds to end
courses.insert(1, "Data Science")    # Inserts at index 1
print("After additions:", courses)

# 5. Removing elements: remove(), pop()
courses.remove("Canva")
popped_item = courses.pop(0)  # Removes item at index 0

# 6. Sorting & Reversing
numbers = [45, 12, 89, 3, 27]
numbers.sort()
print("Sorted numbers:", numbers)

# 7. List Comprehension (Fast list creation)
squares = [x**2 for x in range(1, 6)]
print("Squares list:", squares)

# 1. Creating a Tuple
dimensions = (1920, 1080)
colors = ("Red", "Green", "Blue")

# 2. Accessing elements via indexing
print("Screen Width:", dimensions[0])
print("Primary Color:", colors[0])

# 3. Tuple Unpacking
r, g, b = colors
print(f"Red channel: {r}, Green channel: {g}")

# 4. Tuple Methods: count() and index()
sample = (1, 2, 2, 3, 4, 2)
print("Count of 2:", sample.count(2))  # 3
print("Index of 4:", sample.index(4))  # 4

# Single item tuple MUST have a trailing comma!
single_tuple = ("Python",)  # Notice comma
print(type(single_tuple))  # <class 'tuple'>

# 1. Creating a Dictionary
student = {
    "name": "Harneet Kaur",
    "roll_no": 101,
    "courses": ["Python", "Calligraphy"],
    "is_enrolled": True
}

# 2. Accessing values using keys
print("Student Name:", student["name"])
print("Safe access with .get():", student.get("city", "Not Provided"))

# 3. Adding and Updating key-value pairs
student["city"] = "Ludhiana"  # Adds new key
student["roll_no"] = 105       # Updates existing key

# 4. Dictionary Methods: keys(), values(), items()
print("Keys:", list(student.keys()))
print("Values:", list(student.values()))

# 5. Iterating through dictionary
for key, value in student.items():
    print(f"{key} -> {value}")