Source Map — Level 1: Divisibility, Prime, GCD, LCM¶
এই folder-এর প্রতিটা concept আর problem-এর উৎসের হিসাব। সব Bengali prose, diagram, analogy আর code এই repo-র জন্য নতুন করে লেখা — কোনো বই বা site-এর অনুবাদ/copy নয়। Problem statement কোথাও copy করা হয়নি; শুধু official link দেওয়া আছে।
| Concept / Problem | Source Type | Source Name | Link | How it is used | Copying status |
|---|---|---|---|---|---|
| Divisibility, factor pair, √n trick | Common knowledge | Elementary number theory | — | concept-notes.md section 1-2, নিজের analogy (লাড্ডু, আয়না) | original explanation |
| Trial division prime check | Common knowledge | Standard programming curriculum | — | concept-notes.md section 3, নিজের dry run | original explanation |
| Sieve of Eratosthenes | Reference article | CP-Algorithms | https://cp-algorithms.com/algebra/sieve-of-eratosthenes.html | Algorithm-এর reference; ব্যাখ্যা, grid ছবি ও code নিজের | inspired by source |
| Count Primes (related problem) | Online judge | LeetCode Count Primes | https://leetcode.com/problems/count-primes/ | Problem 015-এর related practice link | official link only |
| Prime factorization, peeling idea | Common knowledge | Elementary number theory | — | concept-notes.md section 5, পেঁয়াজ analogy নিজের | original explanation |
| Largest prime factor (related) | Online judge | Project Euler Problem 3 | https://projecteuler.net/problem=3 | Problem 016-এর related link | official link only |
| SPF sieve variant | Reference article | CP-Algorithms (sieve variants) | https://cp-algorithms.com/algebra/sieve-of-eratosthenes.html | Problem 017 ও concept-notes section 5-এর idea reference; লেখা নিজের | inspired by source |
| Euclidean GCD algorithm | Reference article | CP-Algorithms | https://cp-algorithms.com/algebra/euclid-algorithm.html | Algorithm reference; tile/staircase intuition ও dry run নিজের | inspired by source |
| Extended Euclidean algorithm | Reference article | CP-Algorithms | https://cp-algorithms.com/algebra/extended-euclid-algorithm.html | Problem 019-এর মূল reference; intro ব্যাখ্যা নিজের | inspired by source |
| LCM smallest multiple (related) | Online judge | Project Euler Problem 5 | https://projecteuler.net/problem=5 | Problem 020-এর related link | official link only |
| Euler phi (totient) | Reference article | CP-Algorithms | https://cp-algorithms.com/algebra/phi-function.html | Formula reference; sieve-ভগ্নাংশ intuition নিজের | inspired by source |
| Counting Divisors | Online judge | CSES Problem Set | https://cses.fi/problemset/task/1713 | Problem 024-এর মূল practice link; ব্যাখ্যা নিজের ভাষায় | rewritten problem |
| Sum of Divisors (harder variant) | Online judge | CSES Problem Set | https://cses.fi/problemset/task/1082 | Problem 025-এর harder variant link | official link only |
| Divisibility rules, count factors, coprime, coprime pairs | Common knowledge | Classic exercises | — | Problem 011, 012, 021, 022 — নিজের ভাষায় বানানো অনুশীলনী | original explanation |
| Divisor count/sum exponent formula | Common knowledge | Elementary number theory | — | concept-notes.md section 9, choice-box ছবি নিজের | original explanation |
| Problem note template | This repo | math-problem-note-template.md | ../../templates/math-problem-note-template.md | problems/README.md থেকে রেফার করা | original explanation |
| Modular inverse forward link | This repo | Level 2 folder | ../02-modular-arithmetic/ | Extended GCD ও coprime → inverse cross-reference | original explanation |