150 Curated Coding ProblemsFundamentals of Coding
From Coding Foundations to Algorithmic Thinking
A structured, story-driven progression through 150 carefully selected problems. This is NOT a DSA sheet - it is a coding foundations and mathematical reasoning sheet. Start from printing Hello World, build through arithmetic, conditionals, loops, functions, number theory, bit manipulation, combinatorics, pattern printing, geometry, special numbers, and recursion. Every problem has a real-world story and explanation inside every example. This is the sheet that builds the mathematical intuition behind programming - before you ever touch trees, graphs, or dynamic programming.
Your certificate
150
PreparationStreetCertificate of Completion
150 Problem Sheet
Programming Foundations · 3 sprints · 150 problems
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Your Name
From variables and loops to number theory, recursion and real problems - every one of the 150 solved.
Issued on
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Credential ID
PS-PS150-XXXXXXXX
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150 Problem Sheet
Solve all 150 problems in the sheet. Issued with your name and a verifiable ID.
Sign in to start tracking toward it.
- Sprints
- 3
- Problems
- 150
- Topics
- 17
- Market rating / 10
- 9.6
Skills these companies hire for
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What you'll learn
- 150 story-driven problems - each with a real-world context beginners can relate to
- Zero assumed knowledge - starts from printing Hello World
- Every problem has 3 examples with input, output, AND explanation of the reasoning
- Not a DSA sheet - builds mathematical coding intuition: arithmetic, number theory, patterns, combinatorics
- Covers campus placement test topics: primes, GCD/LCM, Armstrong, palindromes, series, patterns
- Bit manipulation, modular arithmetic, RSA simulation, Huffman coding - industry-relevant math
- Consistent difficulty ramp within each sprint: Easy - Medium - Hard
- Every sprint ends with a 'bring it all together' problem that reuses functions from earlier
Curriculum
3 sprints, in the order that works
Each step builds on the one before it. Open any of them from the sidebar.
- 01
Sprint 1 - Coding Foundations
Basic math & arithmetic, number theory, conditionals & logic, loops & patterns, strings, arrays and data operations
50 problems
- 02
Sprint 2 - Number Theory & Mathematical Algorithms
Sieve of Eratosthenes, prime algorithms, combinatorics, bit manipulation, geometry, matrix operations, special numbers, and pattern printing
50 problems
- 03
Sprint 3 - Advanced Patterns, Recursion & Real Problems
Advanced pattern printing, simulation, stacks/queues from scratch, recursion, special number sequences, mathematical algorithms, and capstone challenges
50 problems
Your path
Start where you are
Pick the track that matches your level - it tells you exactly what to open first.
Absolute beginner
Start at Problem 1. Read the story, understand the example, then code. Do not skip. Each problem builds on the previous. If stuck 30+ minutes, read the explanation and recode from understanding.
Market comparison
How it stacks up against the alternatives
The Only Sheet That Builds the Mathematical Coding Foundation Every Programmer Needs Before DSA
- 9.6
- Overall rating / 10
- Content depth
- 9.2
- Industry relevance
- 9.4
- Hiring alignment
- 9.2
- Practicality
- 9.9
- Production relevance
- 7.2
- Beginner friendliness
- 10
Ahead of the average alternative on 18 of 18 features, by +6.4 points on average.
Zero-to-Code Progression (Absolute Beginner Entry)
Story-Driven Problem Context
Explanation Inside Every Example (Why, Not Just What)
Strict Concept-Before-Use Ordering
Core Coding Foundations (Variables -> Loops -> Functions -> Arrays)
Number Theory Coverage (GCD, LCM, Primes, Sieve, Totient, CRT)
Mathematical Logic (Modular Arithmetic, Combinatorics, Bit Manipulation)
Pattern Printing Depth (15+ Pattern Types)
Special Numbers Coverage (Armstrong, Perfect, Happy, Smith, Keith, Lychrel)
While Loop + Break + Continue - Explicit Teaching
Where most courses fall short
- Practice platforms have thousands of problems - beginners have no idea where to start, jump straight to arrays and graphs
- YouTube playlists explain theory but give no structured progression from absolute zero
- Problem banks have the questions but random difficulty jumps and no story context
- Most paid courses assume you already know basic programming - skip variables, loops, and functions entirely
- No sheet explains WHY the output is correct inside each example - only input/output shown
- Problems on all platforms have no real-world context - just abstract index manipulation
- Nobody explicitly teaches while loop vs for loop, or when to use break vs continue
- Special numbers (Happy, Smith, Keith, Lychrel, Kaprekar) are completely ignored by every major platform
- No sheet teaches bit manipulation from binary representation all the way to XOR tricks
- Nobody teaches RSA, Huffman, Josephus, or Magic Square as coding practice problems - only theory
- No sheet bridges: Hello World -> number theory -> patterns -> recursion -> mathematical algorithms
What this product does instead
- Designed for the beginner who types 'how to start coding' - starts from absolute zero
- Story-driven problems make abstract math tangible and memorable
- Explanation inside every example builds deep understanding, not just pattern matching
- Concept-before-use ordering means no beginner ever feels lost
- 150 curated problems is achievable - gives a sense of progress and completion
- Teaches the mathematical thinking behind programming - not just syntax
- Every Indian engineering student preparing for TCS/Infosys/Wipro/Amazon placement will find every topic they need
- Capstone problems (RSA, Huffman, Magic Square) show beginners what real-world application looks like
- The same JSON schema as premium roadmaps - consistent, renderable, extendable
- Built by someone who solved 5000+ problems - knows exactly what a beginner must build first
Strongest sections
- 10/10
Sprint 1 - Coding Foundations (Problems 1–50)
Only sheet that starts from Hello World and builds through arithmetic, number theory, conditionals, loops (for + while + break + continue), patterns, strings and arrays - every concept taught before use
- 9.9/10
Number Theory Cluster (Problems 6–16, 51–58)
Prime check, GCD Euclidean, LCM, Fibonacci, Armstrong, Perfect, divisors, Sieve, Euler's Totient, modular exponentiation, CRT - the complete mathematical foundation for campus placements
- 9.8/10
Pattern Printing (Problems 29–33, 81–88, 101–110)
15+ distinct pattern types: triangle, inverted triangle, pyramid, hollow rectangle, diamond, butterfly, spiral, checkerboard, hourglass, Floyd variants, alphabet spiral - the most comprehensive pattern set in any beginner sheet
- 9.9/10
Special Numbers Encyclopedia (Problems 89–99, 133–136)
Collatz, Kaprekar, Smith, Amicable, Goldbach, Keith, Mersenne, Lychrel, Josephus, narcissistic - every special number a placement test or competitive programmer ever encounters, in one place
- 9.8/10
Recursion Deep-Dive (Problems 121–132)
Tower of Hanoi, flatten nested list, generate all subsets, all permutations, grid paths, Fibonacci in 3 ways with speed comparison, bitmask power set - recursion taught completely from first principles
- 9.7/10
Capstone Challenges (Problems 143–150)
Sudoku validator, Magic square generator (Siamese method), RSA encryption simulation, Huffman encoding, palindromic subsequence, coin change counting, and a timed 10-problem Grand Finale - shows beginners what real programming looks like
Audience
Who this is for
- Absolute beginners who have never written a line of code
- College students in first or second year building a coding foundation
- Engineering freshers preparing for TCS, Infosys, Wipro, Amazon campus placements
- Career changers entering tech from non-CS backgrounds
- Anyone who tried a problem bank and felt completely lost - this is the prerequisite
Your first step takes five minutes.
Open the first sprint and progress is tracked for you from there.
3 sprints Progress tracked per item Certificate on completion