Python Practice Exercises
40 hands-on problems with full solutions

# Your code here
name = "Ana"
print(f"Hello, {name}!")

a = 7
b = 3
print(a + b)

n = 17
if n % 2 == 0:
    print("even")
else:
    print("odd")

for i in range(1, 11):
    print(i)

n = 100
total = 0
for i in range(1, n + 1):
    total += i
print(total)

a = 12
b = 45
c = 23

print(max(a, b, c))

n = 15

if n % 15 == 0:
    print("FizzBuzz")
elif n % 3 == 0:
    print("Fizz")
elif n % 5 == 0:
    print("Buzz")
else:
    print(n)

for i in range(1, 11):
    print(f"7 × {i} = {7 * i}")

for i in range(10, 0, -1):
    print(i)
print("Liftoff!")

n = 5
result = 1
for i in range(1, n + 1):
    result *= i
print(result)

s = "Python"
print(s[::-1])

word = "Programming"
vowels = "aeiou"

count = 0
for ch in word.lower():
    if ch in vowels:
        count += 1
print(count)

word = "racecar"
cleaned = word.lower()
print(cleaned == cleaned[::-1])

sentence = "the quick brown fox"
print(sentence.title())

sentence = "Python is fun to learn"

for word in sentence.split():
    print(f"{word}: {len(word)}")

phone = "  (555) 123-4567  "
cleaned = ""
for ch in phone:
    if ch.isdigit():
        cleaned += ch
print(cleaned)

word = "swiss"
counts = {}
for ch in word:
    counts[ch] = counts.get(ch, 0) + 1

for ch in word:
    if counts[ch] == 1:
        print(ch)
        break

s = "aaabbbcc"

result = []
prev = s[0]
count = 1

for ch in s[1:]:
    if ch == prev:
        count += 1
    else:
        result.append(f"{prev}{count}")
        prev = ch
        count = 1

result.append(f"{prev}{count}")
print("".join(result))

numbers = [4, 7, 2, 9, 1]
print(sum(numbers))

nums = [1, 2, 3, 4, 5, 6]
evens = [n for n in nums if n % 2 == 0]
print(evens)

nums = [3, 8, 1, 9, 4]

largest = nums[0]
for n in nums[1:]:
    if n > largest:
        largest = n
print(largest)

words = ["apple", "banana", "apple", "cherry", "banana", "apple"]

counts = {}
for w in words:
    counts[w] = counts.get(w, 0) + 1

print(counts)

a = [1, 3, 5]
b = [2, 4, 6]

merged = [item for pair in zip(a, b) for item in pair]
print(merged)

nums = [3, 1, 2, 3, 1, 4, 2]
unique = list(dict.fromkeys(nums))
print(unique)

squares = [n * n for n in range(1, 6)]
print(squares)

transactions = [
    ("food", 12.50),
    ("transport", 3.00),
    ("food", 8.00),
    ("entertainment", 15.00),
    ("food", 5.00),
]

totals = {}
for category, amount in transactions:
    totals[category] = totals.get(category, 0) + amount

print(totals)

a = [1, 2, 3, 4]
b = [3, 4, 5, 6]

common = list(set(a) & set(b))
print(sorted(common))

grid = [
    [1, 2, 3],
    [4, 5, 6],
    [7, 8, 9],
]

transposed = [list(row) for row in zip(*grid)]
for row in transposed:
    print(row)

def greet(name):
    return f"Hello, {name}!"

print(greet("Ana"))
print(greet("Bob"))

def greet(name, greeting="Hello"):
    return f"{greeting}, {name}!"

print(greet("Ana"))
print(greet("Bob", greeting="Hi"))

def min_max(nums):
    return min(nums), max(nums)

nums = [4, 1, 8, 2, 9]
small, large = min_max(nums)
print(f"min={small} max={large}")

def sum_all(*args):
    return sum(args)

print(sum_all(1, 2, 3))
print(sum_all(10))
print(sum_all())

students = [
    {"name": "Ana", "score": 95},
    {"name": "Bob", "score": 88},
    {"name": "Cara", "score": 92},
]

sorted_students = sorted(students, key=lambda s: s["score"], reverse=True)
for s in sorted_students:
    print(f"{s['name']}: {s['score']}")

def factorial(n):
    if n <= 1:
        return 1
    return n * factorial(n - 1)

print(factorial(5))
print(factorial(0))

def apply_twice(func, x):
    return func(func(x))

print(apply_twice(lambda n: n + 10, 5))
print(apply_twice(lambda n: n * 2, 3))

class Dog:
    def __init__(self, name, breed):
        self.name = name
        self.breed = breed

    def bark(self):
        return "Woof!"

d = Dog("Rex", "Labrador")
print(f"{d.name} says {d.bark()}")

class Rectangle:
    def __init__(self, width, height):
        self.width = width
        self.height = height

    @property
    def area(self):
        return self.width * self.height

r = Rectangle(4, 5)
print(f"Area: {r.area}")

class Animal:
    def speak(self):
        return "..."

class Dog(Animal):
    def speak(self):
        return "Woof!"

for animal in [Animal(), Dog()]:
    print(animal.speak())

class ValidationError(Exception):
    pass

def validate_age(age):
    if age < 0:
        raise ValidationError("Age cannot be negative")
    return age

try:
    validate_age(-5)
except ValidationError as e:
    print(f"Caught: {e}")

from dataclasses import dataclass

@dataclass
class Point:
    x: int
    y: int

p1 = Point(3, 4)
p2 = Point(3, 4)

print(p1)
print(p1 == p2)