I came across this problem statement today and thought of sharing it — because the mistake it exposes is more common than you'd think. Task: Check if an array has consecutive duplicate elements. My first instinct? def duplicate(ls, n): if len(ls) == len(set(ls)): return False return True Looks clean. But it's wrong. This returns True for [1, 2, 1] — even though there are NO consecutive duplicates. It just checks if any value repeats anywhere in the list. The correct approach is to compare neighbouring indices: for i in range(len(ls) - 1): if ls[i] == ls[i + 1]: return True return False Same problem. Completely different logic. That small distinction consecutive vs. anywhere: changed everything. This is what I enjoy about Python. It doesn't just test your syntax. It tests how clearly you understand the problem before you write a single line. #Python #DataAnalyst #CodingTips #DataAnalytics
Checking for Consecutive Duplicates in a Python List
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Writing clean, predictable code is just as important as the analysis itself. In Python, understanding memory references is the "hidden" skill that separates scripts that work from scripts that scale. I see many developers struggle with unexpected mutations when handling nested data structures. A simple new_list = old_list doesn't just copy the data; it copies the problem. I just published a deep dive into "Why Your Python List Copies Keep Betraying You." It’s a guide to mastering the copy module so you can stop debugging "impossible" errors and start building more resilient data pipelines. #PythonProgramming #DataAnalytics #TechWriting #CleanCode #MachineLearnin
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Python Clarity Series – Episode 23 Topic: Floating Point Precision Issue 🤯 Why does this happen? print(0.1 + 0.2) Output: 0.30000000000000004 ❗ 👉 This is NOT a Python bug. It’s due to how floating-point numbers are stored in binary. 💡 Fix (when needed): round(0.1 + 0.2, 1) Output: 0.3 💡 Concept: Computers approximate decimal values internally. Important in: ✔ Financial calculations ✔ Data Science Don’t ignore this. #PythonConcepts #FloatingPoint #RealWorldCoding #python #clarity
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You subclass a data processor, override one method, tests pass… then you swap it in and something upstream breaks ⚠️ That’s usually not “bad luck,” it’s a Liskov Substitution Principle violation 🧠 The subclass technically works, but it quietly changed the contract: stricter preconditions, different return guarantees, or new exceptions the parent never had 💥 If callers need to check which subclass they’re dealing with, the abstraction already failed. I broke this down with concrete Python examples 🐍 and when inheritance is just the wrong tool entirely 👉 https://lnkd.in/ewG9ugCc What’s the sneakiest contract violation you’ve shipped without noticing? 💬 #Python #SoftwareEngineering #SOLID #CleanCode #DataScience
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🚀 Day 6/30 of My LeetCode Journey (Python + SQL) Consistency is slowly turning into confidence 💪📈 🔹 **Python Problem of the Day** 👉 *Plus One* Given an integer represented as an array of digits, increment the number by one and return the resulting array. 💡 *Key Concept:* Handling carry from the last digit (especially edge cases like 9 → 10). 🔹 **SQL Problem of the Day** 👉 *Game Play Analysis I* Given a table of player activity, write a query to find the first login date for each player. 💡 *Key Concept:* GROUP BY with MIN() to extract earliest dates. Every day learning something new, refining logic, and improving speed ⚡ Day 6 done ✅ #LeetCode #30DaysChallenge #Python #SQL #CodingJourney #Consistency #ProblemSolving #Learning
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Most implementations of the State pattern in Python look very “clean”. Lots of small classes. A base interface. One class per state. But if you’ve ever worked with one in a real project, you know the downside: transitions are scattered, behaviour is hard to see in one place, and adding new states often means touching multiple files. In today’s video, I rebuild the State pattern in a very different way. Instead of relying on inheritance, I make the state machine explicit as data and use decorators to define transitions. The result is a small, reusable engine where the entire flow becomes visible at a glance. If you’re interested in writing Python that’s easier to reason about and extend, this is a pattern worth understanding. 👉 Watch here: https://lnkd.in/e9Y3xGNF. #python #softwaredesign #designpatterns #statemachine #cleancode
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Learn how to build a predictive model with Python and Scikit-Learn, including data preparation, model selection, and evaluation techniques, with expert tips and real-world examples https://lnkd.in/ge-CSTzq #PredictiveModelWithPython Read the full article https://lnkd.in/ge-CSTzq
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Learn how to build a predictive model with Python and Scikit-Learn, including data preparation, model selection, and evaluation techniques, with expert tips and real-world examples https://lnkd.in/ge-CSTzq #PredictiveModelWithPython Read the full article https://lnkd.in/ge-CSTzq
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Learn how to build a predictive model with Python and Scikit-Learn, including data preparation, model selection, and evaluation techniques, with expert tips and real-world examples https://lnkd.in/ge-CSTzq #PredictiveModelWithPython Read the full article https://lnkd.in/ge-CSTzq
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🚀 Day 12/30 of My LeetCode Journey (Python + SQL) Consistency continues… and the concepts are getting sharper! 💻🔥 🔹 **SQL Problem of the Day** 👉 *Invalid Tweets* Given a `Tweets` table, write a query to find tweet IDs where the content length is strictly greater than 15 characters. 💡 *Key Concept:* String functions like `LENGTH()` for validation. 🔹 **Python Problem of the Day** 👉 *Single Number* Given an array where every element appears twice except one, find that single element. 💡 *Key Concept:* Bit manipulation using XOR for optimal O(n) time and O(1) space. Loving how problem-solving is becoming more intuitive day by day ⚡ Day 12 done ✅ #LeetCode #30DaysChallenge #Python #SQL #CodingJourney #Consistency #ProblemSolving #Learning #BitManipulation
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