Top Python Coding Challenges (LeetCode Basics)

🧠 Top Python Coding Challenges (LeetCode Basics)

Python is one of the most in-demand programming languages in today’s job market. Whether you want to become a software developer, data analyst, or automation engineer, companies expect you to solve coding problems efficiently.

That’s where LeetCode-style Python challenges come in. Practicing them builds your logic, improves your code efficiency, and prepares you for real interview questions.

In this post, we’ll explore 40+ Python coding challenges divided into levels — from beginner to job-ready difficulty. Let’s begin!

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🔰 Why Practice Python Coding Challenges?

Regular coding practice helps you build the mindset of a problem-solver. Here’s what it improves:

• Logical and analytical thinking
• Familiarity with Python built-ins
• Code optimization
• Interview confidence

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🟢 Level 1 — Easy Python Challenges (Logic Building)

Warm-up problems to build comfort with loops, strings, and lists.

• Reverse a string
• Find the maximum number in a list
• Check if a string is a palindrome
• Count vowels in a sentence
• Generate Fibonacci series

def is_palindrome(text):
    return text == text[::-1]

print(is_palindrome("madam"))  # True

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🟡 Level 2 — Intermediate Python Challenges (Data Handling)

Now move on to handling data using lists, sets, and dictionaries.

• Check if two strings are anagrams
• Count word frequency in a sentence
• Merge two sorted lists
• Find common elements between arrays
• Move zeroes to the end of a list

def count_words(text):
    words = text.split()
    return {word: words.count(word) for word in set(words)}

print(count_words("apple banana apple"))

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🔵 Level 3 — Problem Solving & Logic (LeetCode Style)

These are real interview-level questions used in LeetCode and company tests. Learn patterns like two pointers and hash maps.

• Two Sum
• Maximum Subarray Sum
• Missing Number
• Rotate Array
• Merge Intervals

def two_sum(nums, target):
    seen = {}
    for i, n in enumerate(nums):
        if target - n in seen:
            return [seen[target - n], i]
        seen[n] = i

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🔴 Level 4 — Advanced Python Coding Challenges

Common in mid-level developer interviews, these focus on data structures and logic optimization.

• Binary Search
• Group Anagrams
• Longest Substring Without Repeating Characters
• Rotate Matrix
• Valid Sudoku

def binary_search(arr, target):
    low, high = 0, len(arr)-1
    while low <= high:
        mid = (low + high)//2
        if arr[mid] == target:
            return mid
        elif arr[mid] < target:
            low = mid + 1
        else:
            high = mid - 1
    return -1

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🧩 Bonus — Company-Type Automation & Logic Mix

If you want to apply Python in real-world scenarios, try automation challenges like:

• Analyze email or server logs
• Convert CSV to JSON
• Clean Excel sheets using Pandas
• Automate emails with Python scripts

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💼 How to Practice Effectively

1. Start with 2–3 problems daily
2. Focus on writing clean, readable code
3. Use platforms like LeetCode, HackerRank, and Codewars
4. Upload your code on GitHub for visibility
5. Learn multiple solutions to one problem

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🟢 Level 1: Easy — Logic Building (Warm-up)

Focus: Lists, Strings, Loops, Conditions.

#	Challenge	Concept	Example Input → Output
1	Reverse a String	Slicing	"hello" → "olleh"
2	Find Maximum Number	Loops	[3,7,2,9] → 9
3	Sum of Even Numbers	Loop + Modulus	[1,2,3,4,5,6] → 12
4	Count Vowels in String	Loop + Condition	"python" → 1
5	Check Palindrome String	Slicing	"madam" → True
6	Remove Duplicates from List	Set usage	[1,2,2,3,3] → [1,2,3]
7	Second Largest Element	Sorting	[4,10,9,2] → 9
8	Find Factorial	Loop / Recursion	5 → 120
9	Fibonacci Series	Loops	7 → [0,1,1,2,3,5,8]
10	Check Prime	Logic	7 → True

🟡 Level 2: Intermediate — Data Handling Focus: Lists, Dictionaries, Sets, String Manipulation.

#	Challenge	Concept	Example Input → Output
11	Anagram Check	Sorting	"listen", "silent" → True
12	Word Frequency Counter	Dict	"apple banana apple" → {'apple': 2, 'banana': 1}
13	Merge Two Sorted Lists	Pointers	[1,3,5] + [2,4,6] → [1,2,3,4,5,6]
14	Find Common Elements	Set	[1,2,3] & [2,3,4] → [2,3]
15	Move Zeroes to End	List manipulation	[0,1,0,3,12] → [1,3,12,0,0]
16	Longest Word in String	Loop	"I love programming" → "programming"
17	Valid Parentheses	Stack	"([])" → True
18	Unique Characters	Set check	"hello" → False
19	Count Digits & Alphabets	String methods	"abc123" → (3 letters, 3 digits)
20	Matrix Transpose	2D List	[[1,2,3],[4,5,6]] → [[1,4],[2,5],[3,6]]

🔵 Level 3: Problem Solving — Company Interview Level Focus: Algorithms, Patterns, and Optimization.

#	Challenge	Concept	Example Input → Output
21	Two Sum	Hash Map	[2,7,11,15], target=9 → [0,1]
22	Remove Duplicates in Sorted Array	Pointer	[1,1,2] → [1,2]
23	Maximum Subarray Sum	Kadane’s Algorithm	[-2,1,-3,4,-1,2,1,-5,4] → 6
24	Missing Number	Math / XOR	[3,0,1] → 2
25	Majority Element	Dict Counting	[3,2,3] → 3
26	Merge Intervals	Sorting + Merge	[[1,3],[2,6],[8,10]] → [[1,6],[8,10]]
27	Valid Palindrome (Alphanumeric)	Regex / Filter	"A man, a plan, a canal: Panama" → True
28	Rotate Array	Slicing	[1,2,3,4,5,6,7], k=3 → [5,6,7,1,2,3,4]
29	Single Number	XOR	[4,1,2,1,2] → 4
30	Pascal’s Triangle	Nested Loops	5 → [[1],[1,1],[1,2,1],[1,3,3,1],[1,4,6,4,1]]

🔴 Level 4: Coding Logic (Advanced LeetCode Basics)

Focus: Real-time job-level thinking.

#	Challenge	Concept	Example Input → Output
31	Binary Search	Algorithm	[1,2,3,4,5], target=4 → 3
32	Find Intersection Node of Linked Lists	Pointers	A=[4,1,8,4,5], B=[5,6,1,8,4,5] → 8
33	String Compression	Loop + Count	"aaabbc" → "a3b2c1"
34	Group Anagrams	Hash Map	["eat","tea","tan","ate","nat","bat"] → [['eat','tea','ate'],['tan','nat'],['bat']]
35	Length of Longest Substring Without Repeating Characters	Sliding Window	"abcabcbb" → 3
36	Add Two Numbers (Linked List Style)	Math + Logic	[2,4,3] + [5,6,4] → [7,0,8]
37	Valid Sudoku	Set	9×9 board → True/False
38	Find All Duplicates	Count / Set	[4,3,2,7,8,2,3,1] → [2,3]
39	Rotate Matrix	In-place 2D Ops	3×3 matrix → rotated matrix
40	Search Insert Position	Binary Search	[1,3,5,6], target=5 → 2

🧩 Optional (Level 5): Company-Type Automation + Logic Mix

For practical jobs that mix Python logic + company use.

#	Challenge	Use Case
41	Email Log Analyzer	Parse text logs & extract useful data for insights
42	Excel Auto Formatter	Automate Excel cleaning and formatting using Pandas
43	Folder Duplicate Cleaner	Detect and remove duplicate files using hashing
44	API Response Validator	Validate and verify JSON responses from APIs
45	CSV → JSON Converter	Convert CSV data into structured JSON for automation

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🏁 Conclusion

Learning Python is simple — but becoming job-ready requires applying logic through real coding problems. Regular practice of LeetCode-style Python challenges strengthens your programming mindset and boosts your technical interview success.

Start today — one challenge a day keeps the fear of coding away!

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❓ Frequently Asked Questions (FAQs)

Q1. Where can I practice these Python coding challenges?

You can use LeetCode, HackerRank, or Jupyter Notebook on your system.

Q2. How many problems should I solve daily?

Start with 2–3 daily, then move to 5 as you gain confidence.

Q3. Are these problems asked in real interviews?

Yes, most entry-level and mid-level developer interviews use similar logic-based questions.

Q4. Is Python alone enough to get a job?

Python plus problem-solving, projects, and web or data skills can definitely get you hired.

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📚 Next Blog: Integer to Roman – Python Coding Challenges

After learning how to convert Roman numerals to integers, it’s time to go the other way! In our next Python challenge, Integer to Roman, you’ll learn how to convert numbers into Roman numerals using mapping, loops, and efficient algorithms. A great exercise for coding interviews and mastering number/string logic!

👉 Read Next: Integer to Roman in Python