blackhatinside's blog

By blackhatinside, 2 years ago, In English

Hello CF community,

So recently I came across the Leetcode Problem, where we had to find a peak in the given unsorted array. And the most optimized approach was to use Binary Search. Quite interesting concept! I was puzzled so I researched a bit on the topic and came across an interesting term. The Binary hyperparameter search. If you find time, do check this out. I would also like to know more about such problems where the solutions are interestingly out of the box.

I felt writing this simple blog will help many beginners like me out there who never knew such a concept existed. So please try to share in here or in my DM if you know any such interesting topics which can broaden our knowledge on some well known concept.

Such topics are the reason why I love programming. It challenges my logical thinking ability. Hope it's the same for you too. :)

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By blackhatinside, 2 years ago, In English

Can anyone tell me how we derived at the Mathematical Formula for number of multipliers of k in the given range [1 to N] as

(k — 1) / (n — 1).

Problem Link

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By blackhatinside, 2 years ago, In English

Hey Community,

Below, you will find a list of simple CP tools which I use on a regular basis for self analysis. I would love to know about any other active CP Analyzer tools (for CF, Leetcode, Codechef, GFG, etc.), learning resources and browser extensions.



Javascript Extension to auto-commit your leetcode, GFG & atcoder solutions to GitHub

If any other useful tools are missing please try to add those in the comment section. Hope my blog is helpful to this community If you love it, then do share with your CP friends. Happy Coding :) Thank you!


Practice (Easy to Difficult Website Ranking)


  • Min Max Heaps

  • Hashing, Sets, Multisets

  • Trees

    • Binary Search Tree (BST)
    • Tries, Segment Tree, Fenwick Tree (or Binary Indexed Tree)
    • Minimum Spanning Tree, Suffix Tree
    • Disjoint Set (or Union-Find)
    • Trie
  • Graphs

    • Simple Nodes (numbers)
    • Complex Nodes (objects)


  • Arrays:

    • Bit Masking
    • Prefix Sum — Precomputations
    • Sliding Window — Two pointers
    • Kadane's Algorithm
    • Josephus Algorithm
    • Square Root Decomposition
    • MO Algorithm
  • String

    • Rabin-Karp Algorithm
    • Manacher's Algorithm
    • Z algorithm
  • Greedy Approach, Bruteforce

    • Recursion
    • Backtracking
  • Optimization

    • Memoization
    • Dynamic Programming
    • Binary Search
    • Divide and Conquer
  • Math

    • Binary hyperparameter search
    • Logarithmic Exponentiation
    • Chinese Remainder Theorem
    • Sprague-Grundy theorem
    • Convex Hull Construction
    • Stable marriage problem
    • Fast-Fourier Transform
    • Sieve of Eratosthenes
    • Binary Exponentiation
    • Euclidean Algorithm
    • Sweep Line Algorithm
    • Gaussian Elimination
    • Manhattan Distance
    • Catalan Numbers
    • Pigeonhole
  • Graph

    • Breadth First Search M1
    • Depth First Search
    • Flood Fill
    • Shortest Path
    • Dijkstra Algorithm
    • Floyd Warshall Algorithm
    • Bellman Ford Algorithm
    • Prims Algorithm
    • Krushal Algorithm
    • Topological Sort
    • Lowest Common Ancestor
    • Euler Tour of Tree
    • Bipartite Graph
    • Strongly Connected Component
    • Heavy-light Decomposition

Feel Free to mention below in the comments, if any important topic is missing in this list (no need to spread hatred comments instead). I hope my blog reaches the right people who are in need of help. I never had a good guidance. At least you all should.

Thank you. Happy Coding :)

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By blackhatinside, 2 years ago, In English

Is there any rank filter or option in Codeforces to find out the list of people who made the highest submissions through a Particular Language? (in my case, Python) I just wanted to learn various CP optimization techniques used by the top Python coders in here. If you feel you too are facing the same issue or wish to know the same thing, do feel free to upvote this blog. As far as I know pajenegod is the highest rated Python coder in my knowledge. Please correct me if am wrong. Thank you friends, have a blissful day :) ****

UPD: conqueror_of_tourist is now the highest rated Python Code in Codeforces

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