Codility Training - Complete 8-Week Lessons

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Codility Training - Complete 8-Week Lessons

Comprehensive lessons for your 8-week Codility preparation journey!

📚 Complete Lesson Files

✅ Week 1: Foundations (TypeScript + Basic DSA)

Topics: - Day 1: TypeScript basics (functions, arrays, loops) - Day 2: Big-O notation (O(1), O(n), O(n²), O(log n)) - Days 3-4: Array manipulation - Day 5: Edge case handling - Day 6: Review and practice

Challenges: BinaryGap, OddOccurrencesInArray, CyclicRotation, TapeEquilibrium, PermMissingElem

✅ Week 2: Counting, Prefix Sum & Hash Maps

File: week2-counting-prefix-hashmaps.md

Topics: - Days 8-9: Counting elements (boolean arrays vs hash maps) - Days 10-11: Prefix sum technique ⭐ VERY IMPORTANT! - Day 12: Hash map patterns - Day 14: Mock Test 1 (45 min, target 70%+)

Challenges: PermCheck, FrogJmp, MissingInteger, FrogRiverOne, GenomicRangeQuery

✅ Week 3: Sorting, Greedy & Basic Math

File: week3-sorting-greedy-math.md

Topics: - Days 15-16: Sorting algorithms and patterns - Day 17: Greedy algorithms - Day 18: Simple math in DSA - Day 19: Extra sorting practice - Day 21: Mock Test 2 (60 min, target 75%+)

Challenges: Distinct, MaxProductOfThree, Triangle, TieRopes, CountDiv, PassingCars

✅ Week 4: Stacks, Queues, Leaders ⭐ MAJOR WEEK!

File: week4-stacks-queues-leaders.md

Topics: - Day 22: Stack fundamentals - Day 23: Stack simulation (Fish, StoneWall) - Day 24: Leaders & Dominator (Boyer-Moore) - Days 25-27: Review and advanced practice - Day 28: Mock Test 3 (70 min, target 80%+)

Challenges: Brackets, Fish, StoneWall ⭐, Dominator, EquiLeader

Why Important: Stack problems appear in 40%+ of Codility tests!

✅ Week 5: Maximum Slices + DP Basics

File: week5-slices-dp.md

Topics: - Day 29: Kadane's algorithm ⭐ - Day 30: Max double slice (tricky!) - Day 31: DP fundamentals - Day 32: DP practice - Day 35: Mock Test 4 (75 min, target 80-85%+)

Challenges: MaxSliceSum, MaxProfit, MaxDoubleSliceSum, NumberSolitaire

Key Pattern: Kadane's algorithm is essential!

✅ Week 6: Binary Search, Peaks, Flags, Sieve

File: week6-binary-search-peaks-sieve.md

Topics: - Day 36: Binary search (on array, on answer) - Day 37: Sieve of Eratosthenes - Day 38: Peaks - Day 39: Flags ⭐ VERY COMMON! - Day 40: Rectangle / Geometry - Day 42: Mock Test 5 (75-90 min, target 85%+)

Challenges: MinMaxDivision, CountFactors, CountSemiprimes, Peaks, Flags, ChocolatesByNumbers

✅ Week 7: Reinforcement + Review

File: week7-review-practice.md

Topics: - Days 43-44: Array medium review (LeetCode) - Day 45: Stack & leader review - Day 46: Binary search review - Day 47: Prefix sum review - Day 48: Mini Mock Test (60 min, target 90%+) - Day 49: Free review day

Focus: Fill gaps, increase speed, build confidence

✅ Week 8: Final Codility Simulation Week

File: week8-final-mocks.md

Topics: - Day 51: Full Mock Test A (90 min) - Day 52: Review results - Day 53: Full Mock Test B (90 min) - Day 54: Review results - Day 55: Full Mock Test C (90 min) - Day 56: Final self-assessment

Goal: 85-90% correctness + optimized performance

🎯 Quick Pattern Reference

Most Important Patterns

Pattern	When to Use	Time	Lesson
Prefix Sum	Range queries	O(n) build, O(1) query	Week 2
Stack	Matching, simulation	O(n)	Week 4
Kadane's	Max subarray	O(n)	Week 5
Boyer-Moore	Majority element	O(n)	Week 4
Binary Search	Sorted data, optimization	O(log n)	Week 6
Greedy	Local → global optimum	Varies	Week 3
Two Pointers	Pairs, subarrays	O(n)	Week 1, 7
Sieve	Prime numbers	O(n log log n)	Week 6

Critical Problems to Master

🔥 Must Know: 1. GenomicRangeQuery - Multiple prefix sums (Week 2) 2. StoneWall - Stack simulation (Week 4) ⭐ VERY COMMON 3. Fish - Stack with conditions (Week 4) 4. Flags - Greedy + optimization (Week 6) ⭐ VERY COMMON 5. MaxDoubleSliceSum - Two DP arrays (Week 5) 6. EquiLeader - Boyer-Moore application (Week 4)

📊 Learning Path

Week by Week Goals

Week 1: Foundation - ✅ Master TypeScript basics - ✅ Understand Big-O - ✅ Handle edge cases

Week 2: Core Techniques - ✅ Counting patterns - ✅ Prefix sums (CRITICAL!) - ✅ Hash maps - 🎯 Target: 70%+ on mock test

Week 3: Algorithms - ✅ Sorting strategies - ✅ Greedy thinking - ✅ Math optimization - 🎯 Target: 75%+ on mock test

Week 4: Advanced Structures - ✅ Stack mastery - ✅ Queue operations - ✅ Boyer-Moore algorithm - 🎯 Target: 80%+ on mock test

Week 5: Dynamic Programming - ✅ Kadane's algorithm - ✅ DP fundamentals - ✅ State transitions - 🎯 Target: 80-85%+ on mock test

Week 6: Optimization - ✅ Binary search patterns - ✅ Prime numbers (Sieve) - ✅ Complex greedy (Flags, Peaks) - 🎯 Target: 85%+ on mock test

Week 7: Consolidation - ✅ Review all patterns - ✅ Increase speed - ✅ Fill gaps - 🎯 Target: 90%+ on easier, 75%+ on hard

Week 8: Final Preparation - ✅ Full-length simulations - ✅ Time management - ✅ Confidence building - 🎯 Goal: 85-90% overall

💡 Study Tips

How to Use These Lessons

Daily Routine: 1. Read the lesson (20-30 min) - Understand concepts thoroughly - Take notes on patterns

Practice challenges (60-90 min)
Try solving yourself first
Compare with provided solutions
Understand WHY solution works
Track progress (10 min)
Use the web app
Mark completed tasks
Note difficulties
Review (10-15 min)
What did you learn?
What was difficult?
What to practice more?

Maximizing Learning

Do: - ✅ Solve problems yourself before looking at solutions - ✅ Understand the pattern, not just memorize code - ✅ Practice edge cases - ✅ Time yourself - ✅ Review mistakes

Don't: - ❌ Just copy solutions without understanding - ❌ Skip the "easy" problems - ❌ Ignore time complexity - ❌ Forget to test edge cases - ❌ Give up when stuck (take break, come back)

🚀 Success Metrics

By End of Week 4

Can solve easy problems in < 5 minutes
Can solve medium problems in < 15 minutes
Know basic patterns (prefix sum, stack, counting)
Comfortable with TypeScript

By End of Week 6

Can solve most medium problems in < 12 minutes
Can attempt hard problems
Recognize patterns immediately
Handle edge cases automatically

By End of Week 8

Can solve easy problems in < 3 minutes
Can solve medium problems in < 10 minutes
Can solve hard problems in < 20 minutes
Ready for 85-90% on real test!

📖 Additional Resources

Codility Resources

Practice Platforms

LeetCode - Easy/Medium problems
HackerRank - Algorithm practice
CodeSignal - Interview prep

TypeScript

🎓 Final Words

You have everything you need: - 8 weeks of structured lessons ✅ - 50+ solved challenges ✅ - Complete pattern reference ✅ - Mock tests for practice ✅

Your success formula:

Consistent Practice
+ Pattern Recognition
+ Time Management
+ Edge Case Handling
= 85-90% Success Rate! 🎯

Remember: - Start with Week 1, follow the order - Don't rush - understanding > speed initially - Speed comes with practice - Use the web app to track progress - Review difficult problems multiple times

📞 Need Help?

If you're stuck: 1. Re-read the lesson explanation 2. Trace through the example step-by-step 3. Try a simpler version of the problem 4. Review the pattern from earlier weeks 5. Take a break and come back fresh

You've got this! 💪

Start your journey with Week 1: Foundations →

Last Updated: 2025 Total Lessons: 8 weeks Total Challenges: 50+ Goal: 85-90% Codility Test Success! 🚀

# Codility Training - Complete 8-Week Lessons

Comprehensive lessons for your 8-week Codility preparation journey!

---

## 📚 Complete Lesson Files

### ✅ Week 1: Foundations (TypeScript + Basic DSA)
**File**: [week1-foundations.md](week1-foundations.md)

**Topics**:
- Day 1: TypeScript basics (functions, arrays, loops)
- Day 2: Big-O notation (O(1), O(n), O(n²), O(log n))
- Days 3-4: Array manipulation
- Day 5: Edge case handling
- Day 6: Review and practice

**Challenges**: BinaryGap, OddOccurrencesInArray, CyclicRotation, TapeEquilibrium, PermMissingElem

---

### ✅ Week 2: Counting, Prefix Sum & Hash Maps
**File**: [week2-counting-prefix-hashmaps.md](week2-counting-prefix-hashmaps.md)

**Topics**:
- Days 8-9: Counting elements (boolean arrays vs hash maps)
- Days 10-11: Prefix sum technique ⭐ VERY IMPORTANT!
- Day 12: Hash map patterns
- Day 14: **Mock Test 1** (45 min, target 70%+)

**Challenges**: PermCheck, FrogJmp, MissingInteger, FrogRiverOne, GenomicRangeQuery

---

### ✅ Week 3: Sorting, Greedy & Basic Math
**File**: [week3-sorting-greedy-math.md](week3-sorting-greedy-math.md)

**Topics**:
- Days 15-16: Sorting algorithms and patterns
- Day 17: Greedy algorithms
- Day 18: Simple math in DSA
- Day 19: Extra sorting practice
- Day 21: **Mock Test 2** (60 min, target 75%+)

**Challenges**: Distinct, MaxProductOfThree, Triangle, TieRopes, CountDiv, PassingCars

---

### ✅ Week 4: Stacks, Queues, Leaders ⭐ MAJOR WEEK!
**File**: [week4-stacks-queues-leaders.md](week4-stacks-queues-leaders.md)

**Topics**:
- Day 22: Stack fundamentals
- Day 23: Stack simulation (Fish, StoneWall)
- Day 24: Leaders & Dominator (Boyer-Moore)
- Days 25-27: Review and advanced practice
- Day 28: **Mock Test 3** (70 min, target 80%+)

**Challenges**: Brackets, Fish, StoneWall ⭐, Dominator, EquiLeader

**Why Important**: Stack problems appear in 40%+ of Codility tests!

---

### ✅ Week 5: Maximum Slices + DP Basics
**File**: [week5-slices-dp.md](week5-slices-dp.md)

**Topics**:
- Day 29: Kadane's algorithm ⭐
- Day 30: Max double slice (tricky!)
- Day 31: DP fundamentals
- Day 32: DP practice
- Day 35: **Mock Test 4** (75 min, target 80-85%+)

**Challenges**: MaxSliceSum, MaxProfit, MaxDoubleSliceSum, NumberSolitaire

**Key Pattern**: Kadane's algorithm is essential!

---

### ✅ Week 6: Binary Search, Peaks, Flags, Sieve
**File**: [week6-binary-search-peaks-sieve.md](week6-binary-search-peaks-sieve.md)

**Topics**:
- Day 36: Binary search (on array, on answer)
- Day 37: Sieve of Eratosthenes
- Day 38: Peaks
- Day 39: Flags ⭐ VERY COMMON!
- Day 40: Rectangle / Geometry
- Day 42: **Mock Test 5** (75-90 min, target 85%+)

**Challenges**: MinMaxDivision, CountFactors, CountSemiprimes, Peaks, Flags, ChocolatesByNumbers

---

### ✅ Week 7: Reinforcement + Review
**File**: [week7-review-practice.md](week7-review-practice.md)

**Topics**:
- Days 43-44: Array medium review (LeetCode)
- Day 45: Stack & leader review
- Day 46: Binary search review
- Day 47: Prefix sum review
- Day 48: **Mini Mock Test** (60 min, target 90%+)
- Day 49: Free review day

**Focus**: Fill gaps, increase speed, build confidence

---

### ✅ Week 8: Final Codility Simulation Week
**File**: [week8-final-mocks.md](week8-final-mocks.md)

**Topics**:
- Day 51: **Full Mock Test A** (90 min)
- Day 52: Review results
- Day 53: **Full Mock Test B** (90 min)
- Day 54: Review results
- Day 55: **Full Mock Test C** (90 min)
- Day 56: Final self-assessment

**Goal**: 85-90% correctness + optimized performance

---

## 🎯 Quick Pattern Reference

### Most Important Patterns

| Pattern | When to Use | Time | Lesson |
|---------|-------------|------|--------|
| **Prefix Sum** | Range queries | O(n) build, O(1) query | Week 2 |
| **Stack** | Matching, simulation | O(n) | Week 4 |
| **Kadane's** | Max subarray | O(n) | Week 5 |
| **Boyer-Moore** | Majority element | O(n) | Week 4 |
| **Binary Search** | Sorted data, optimization | O(log n) | Week 6 |
| **Greedy** | Local → global optimum | Varies | Week 3 |
| **Two Pointers** | Pairs, subarrays | O(n) | Week 1, 7 |
| **Sieve** | Prime numbers | O(n log log n) | Week 6 |

### Critical Problems to Master

🔥 **Must Know**:
1. **GenomicRangeQuery** - Multiple prefix sums (Week 2)
2. **StoneWall** - Stack simulation (Week 4) ⭐ VERY COMMON
3. **Fish** - Stack with conditions (Week 4)
4. **Flags** - Greedy + optimization (Week 6) ⭐ VERY COMMON
5. **MaxDoubleSliceSum** - Two DP arrays (Week 5)
6. **EquiLeader** - Boyer-Moore application (Week 4)

---

## 📊 Learning Path

### Week by Week Goals

**Week 1**: Foundation
- ✅ Master TypeScript basics
- ✅ Understand Big-O
- ✅ Handle edge cases

**Week 2**: Core Techniques
- ✅ Counting patterns
- ✅ Prefix sums (CRITICAL!)
- ✅ Hash maps
- 🎯 **Target**: 70%+ on mock test

**Week 3**: Algorithms
- ✅ Sorting strategies
- ✅ Greedy thinking
- ✅ Math optimization
- 🎯 **Target**: 75%+ on mock test

**Week 4**: Advanced Structures
- ✅ Stack mastery
- ✅ Queue operations
- ✅ Boyer-Moore algorithm
- 🎯 **Target**: 80%+ on mock test

**Week 5**: Dynamic Programming
- ✅ Kadane's algorithm
- ✅ DP fundamentals
- ✅ State transitions
- 🎯 **Target**: 80-85%+ on mock test

**Week 6**: Optimization
- ✅ Binary search patterns
- ✅ Prime numbers (Sieve)
- ✅ Complex greedy (Flags, Peaks)
- 🎯 **Target**: 85%+ on mock test

**Week 7**: Consolidation
- ✅ Review all patterns
- ✅ Increase speed
- ✅ Fill gaps
- 🎯 **Target**: 90%+ on easier, 75%+ on hard

**Week 8**: Final Preparation
- ✅ Full-length simulations
- ✅ Time management
- ✅ Confidence building
- 🎯 **Goal**: 85-90% overall

---

## 💡 Study Tips

### How to Use These Lessons

**Daily Routine**:
1. **Read the lesson** (20-30 min)
   - Understand concepts thoroughly
   - Take notes on patterns

2. **Practice challenges** (60-90 min)
   - Try solving yourself first
   - Compare with provided solutions
   - Understand WHY solution works

3. **Track progress** (10 min)
   - Use the web app
   - Mark completed tasks
   - Note difficulties

4. **Review** (10-15 min)
   - What did you learn?
   - What was difficult?
   - What to practice more?

### Maximizing Learning

**Do**:
- ✅ Solve problems yourself before looking at solutions
- ✅ Understand the pattern, not just memorize code
- ✅ Practice edge cases
- ✅ Time yourself
- ✅ Review mistakes

**Don't**:
- ❌ Just copy solutions without understanding
- ❌ Skip the "easy" problems
- ❌ Ignore time complexity
- ❌ Forget to test edge cases
- ❌ Give up when stuck (take break, come back)

---

## 🚀 Success Metrics

### By End of Week 4
- Can solve easy problems in < 5 minutes
- Can solve medium problems in < 15 minutes
- Know basic patterns (prefix sum, stack, counting)
- Comfortable with TypeScript

### By End of Week 6
- Can solve most medium problems in < 12 minutes
- Can attempt hard problems
- Recognize patterns immediately
- Handle edge cases automatically

### By End of Week 8
- Can solve easy problems in < 3 minutes
- Can solve medium problems in < 10 minutes
- Can solve hard problems in < 20 minutes
- **Ready for 85-90% on real test!**

---

## 📖 Additional Resources

### Codility Resources
- [Official Codility Lessons](https://app.codility.com/programmers/lessons/)
- [Codility Training Tasks](https://app.codility.com/programmers/)

### Practice Platforms
- [LeetCode](https://leetcode.com/) - Easy/Medium problems
- [HackerRank](https://www.hackerrank.com/) - Algorithm practice
- [CodeSignal](https://codesignal.com/) - Interview prep

### TypeScript
- [TypeScript Handbook](https://www.typescriptlang.org/docs/)
- [TypeScript Playground](https://www.typescriptlang.org/play)

---

## 🎓 Final Words

**You have everything you need**:
- 8 weeks of structured lessons ✅
- 50+ solved challenges ✅
- Complete pattern reference ✅
- Mock tests for practice ✅

**Your success formula**:
```
Consistent Practice
+ Pattern Recognition
+ Time Management
+ Edge Case Handling
= 85-90% Success Rate! 🎯
```

**Remember**:
- Start with Week 1, follow the order
- Don't rush - understanding > speed initially
- Speed comes with practice
- Use the web app to track progress
- Review difficult problems multiple times

---

## 📞 Need Help?

If you're stuck:
1. Re-read the lesson explanation
2. Trace through the example step-by-step
3. Try a simpler version of the problem
4. Review the pattern from earlier weeks
5. Take a break and come back fresh

**You've got this!** 💪

Start your journey with [Week 1: Foundations](week1-foundations.md) →

---

Last Updated: 2025
Total Lessons: 8 weeks
Total Challenges: 50+
Goal: 85-90% Codility Test Success! 🚀

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