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- Warmup
- Implementation
- Strings
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- Search
- Graph Theory
- Greedy
- Dynamic Programming
- Constructive Algorithms
- Bit Manipulation
- Recursion
- Game Theory
- NP Complete
- Fundamentals
- Number Theory
- Combinatorics
- Algebra
- Geometry
- Probability
- Linear Algebra Foundations
- Introduction
- Strings
- BigNumber
- Data Structures
- Object Oriented Programming
- Exception Handling
- Advanced
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Solve Me First | O(1) | O(1) | Easy | 1 | |||
| Simple Array Sum | O(n) | O(1) | Easy | 10 | |||
| Compare the Triplets | O(1) | O(1) | Easy | 10 | |||
| A Very Big Sum | O(n) | O(1) | Easy | 10 | |||
| Diagonal Difference | O(n) | O(1) | Easy | 10 | |||
| Plus Minus | O(n) | O(1) | Easy | 10 | |||
| Staircase | O(n) | O(n) | Easy | 10 | |||
| Mini-Max Sum | O(1) | O(1) | Easy | 10 | |||
| Time Conversion | O(1) | O(1) | Easy | 15 | |||
| Birthday Cake Candles | O(n) | O(1) | Easy | 10 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Intro to Tutorial Challenges | O(n) | O(1) | Easy | 30 | |||
| Insertion Sort - Part 1 | O(n) | O(1) | Easy | 30 | |||
| Insertion Sort - Part 2 | O(n^2) | O(1) | Easy | 30 | |||
| Correctness and the Loop Invariant | O(n^2) | O(1) | Easy | 30 | |||
| Running Time of Algorithms | O(n^2) | O(1) | Easy | 30 | |||
| Quicksort 1 - Partition | O(n) | O(n) | Easy | 10 | |||
| Quicksort 2 - Sorting | O(n^2) | O(n) | Easy | 30 | |||
| Quicksort In-Place | O(n^2) | O(log(n)) | Medium | 35 | |||
| Running Time of Quicksort | O(n log(n)) | O(log(n)) | Easy | 35 | |||
| Counting Sort 1 | O(n+k) | O(k) | Easy | 30 | value of k in this problem is 100 | ||
| Counting Sort 2 | O(n+k) | O(n+k) | Easy | 30 | Value of k is 100 in this problem. | ||
| Counting Sort 3 | O(n+k) | O(k) | Easy | 30 | |||
| The Full Counting Sort | O(n+k) | O(n+k) | Medium | 40 | |||
| Closest Numbers | O(n log(n)) | O(n) | Easy | 35 | |||
| Find the Median | O(n log(n)) | O(n) | Easy | 35 | |||
| Insertion Sort Advanced Analysis |
| Advanced | 50 | ||||
| Fraudulent Activity Notifications | O(n^2) | O(n) | Medium | 40 | |||
| Lily's Homework | O(n log(n)) | O(n) | Medium | 40 | |||
| Big Sorting | O(n log(n)) | O(n) | Easy | 20 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Hackerland Radio Transmitters | O(n log(n)) | O(n) | Medium | 25 | |||
| Ice Cream Parlor | O(n) | O(n) | Easy | 30 | |||
| Binary Search: Ice Cream Parlor | O(n) | O(n) | Easy | 35 | |||
| Gridland Metro |
| O(k) | O(k) | Medium | 25 | k = number of tracks | |
| Missing Numbers | O(n) | O(n) | Easy | 45 | |||
| Minimum Loss | O(n log(n)) | O(n) | Medium | 35 | |||
| KnightL on a Chessboard |
| Medium | 35 | ||||
| Pairs | O(n log(n)) | O(n) | Medium | 50 | |||
| Sherlock and Array | O(n) | O(n) | Easy | 40 | |||
| Maximum Subarray Sum |
| Hard | 65 | ||||
| Connected Cells in a grid |
| Medium | 50 | ||||
| Short Palindrome |
| Medium | 40 | ||||
| Maximizing Mission Points |
| Hard | 70 | ||||
| Count Luck |
| Medium | 50 | ||||
| Cut the Tree |
| Medium | 50 | ||||
| Making Candies |
| Hard | 45 | ||||
| Gena Playing Hanoi |
| Medium | 50 | ||||
| Beautiful Quadruples |
| Medium | 50 | ||||
| Bike Racers |
| Hard | 65 | ||||
| Task Scheduling |
| Advanced | 70 | ||||
| Similar Pair |
| Advanced | 70 | ||||
| Absolute Element Sums |
| Hard | 70 | ||||
| Sorted Subsegments |
| Hard | 80 | ||||
| Distant Pairs |
| Expert | 80 | ||||
| King Richard's Knights |
| Hard | 80 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Lena Sort |
| Medium | 30 | ||||
| Flipping the Matrix | O(n^2) | O(n^2) | Medium | 30 | |||
| Gaming Array |
| Medium | 35 | ||||
| New Year Chaos |
| Medium | 40 | ||||
| Bonetrousle |
| Medium | 50 | ||||
| Yet Another KMP Problem |
| Hard | 60 | ||||
| Beautiful 3 Set |
| Hard | 60 | ||||
| Inverse RMQ |
| Hard | 60 | ||||
| Two Subarrays |
| Expert | 70 | ||||
| Lovely Triplets |
| Advanced | 80 | ||||
| Array Construction |
| Advanced | 80 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Lonely Integer | O(n) | O(1) | Easy | 20 | |||
| Maximizing XOR |
| Easy | 30 | ||||
| Counter game |
| Medium | 30 | ||||
| Xor-sequence |
| Medium | 40 | ||||
| Sum vs XOR | O(n log(n)) | O(1) | Easy | 20 | |||
| The Great XOR |
| Medium | 25 | ||||
| Flipping bits |
| Easy | 40 | ||||
| Yet Another Minimax Problem |
| Medium | 30 | ||||
| Sansa and XOR |
| Medium | 30 | ||||
| AND Product |
| Medium | 40 | ||||
| Xoring Ninja |
| Hard | 55 | ||||
| Cipher |
| Medium | 50 | ||||
| XOR Matrix |
| Hard | 50 | ||||
| What's Next? |
| Medium | 50 | ||||
| String Transmission |
| Hard | 60 | ||||
| A or B |
| Medium | 50 | ||||
| Manipulative Numbers |
| Hard | 55 | ||||
| Stone game |
| Hard | 70 | ||||
| 2's complement |
| Advanced | 70 | ||||
| Changing Bits |
| Advanced | 70 | ||||
| XOR key |
| Advanced | 80 | ||||
| Maximizing the Function |
| Hard | 70 | ||||
| XOR Subsequences |
| Advanced | 80 | ||||
| Iterate It |
| Expert | 90 | ||||
| Hamming Distance |
| Expert | 150 | ||||
| Mixing proteins |
| Hard | 80 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| The Power Sum |
| Easy | 20 | ||||
| Crossword Puzzle |
| Medium | 30 | ||||
| Recursive Digit Sum |
| Medium | 30 | ||||
| Simplified Chess Engine |
| Medium | 40 | ||||
| Password er |
| Medium | 40 | ||||
| Artithmetic Expressions |
| Hard | 40 | ||||
| K Factorization |
| Hard | 50 | ||||
| Bowling Pins |
| Advanced | 60 | ||||
| Simplified Chess Engine II |
| Hard | 60 | ||||
| Repetitive K-Sums |
| Advanced | 150 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Game of Stones | O(n) | O(1) | Easy | 15 | |||
| Tower Breakers |
| Easy | 15 | ||||
| A Chessboard Game |
| Easy | 15 | ||||
| Introduction to Nim Game |
| Easy | 15 | ||||
| Misère Nim |
| Easy | 20 | ||||
| Nimble Game |
| Easy | 20 | ||||
| Alice and Bob's Silly Game |
| Medium | 30 | ||||
| Poker Nim |
| Easy | 20 | ||||
| Tower Breakers, Revisited! |
| Medium | 25 | ||||
| Tower Breakers, Again! |
| Medium | 30 | ||||
| Zero-Move Nim |
| Medium | 50 | ||||
| Chessboard Game, Again! |
| Medium | 30 | ||||
| Digits Square Board |
| Medium | 35 | ||||
| Fun Game |
| Medium | 40 | ||||
| Stone Division |
| Hard | 50 | ||||
| Chocolate in Box |
| Medium | 70 | ||||
| Kitty and Katty |
| Medium | 80 | ||||
| Powers Game |
| Medium | 50 | ||||
| Deforestation |
| Medium | 50 | ||||
| Bob and Ben |
| Medium | 50 | ||||
| Tower Breakers - The Final Battle |
| Medium | 50 | ||||
| Simple Game |
| Hard | 60 | ||||
| Permutation game |
| Medium | 70 | ||||
| Move the Coins |
| Hard | 60 | ||||
| Play on benders |
| Medium | 70 | ||||
| New Year Game |
| Medium | 60 | ||||
| Stone Piles |
| Hard | 80 | ||||
| Chocolate Game |
| Hard | 90 | ||||
| Manasa and Prime game |
| Hard | 90 | ||||
| Vertical Rooks |
| Medium | 90 | ||||
| A stones game |
| Medium | 90 | ||||
| Tastes Like Winning |
| Expert | 100 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Walking the Approximate Longest Path |
| Hard | 70 | ||||
| Sam's Puzzle (Approximate) |
| Advanced | 85 | ||||
| Spies, Revised |
| Expert | 100 | ||||
| TBS Problem |
| Expert | 100 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Class vs. Instance | N/A | N/A | Easy | 30 | |||
| Inheritance | O(n) | O(1) | Easy | 30 | |||
| Abstract Classes | N/A | N/A | Easy | 30 | |||
| Complex Numbers | O(1) | O(1) | Easy | 30 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Arrays - DS | O(n) | O(n) | Easy | 10 | |||
| 2D Array - DS | O(1) | O(1) | Easy | 15 | |||
| Sparse Arrays | O(n + q) | O(n + q) | Medium | 25 | n = number of input strings, q = number of queries | ||
| Dynamic Array | O(q) | O(n) | Easy | 15 | q = Number of queries |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Print the Elements of a Linked List | O(n) | O(1) | Easy | 5 | |||
| Reverse a Linked List | O(n) | O(1) | Easy | 5 | |||
| Compare Two Linked Lists | O(n) | O(1) | Easy | 5 | |||
| Delete a node | O(n) | O(1) | Easy | 5 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Tree: Preorder Traversal | O(n) | O(n) | Easy | 10 | |||
| Swap Nodes [Algo] | O(n) | O(n) | Medium | 40 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Self Balancing Tree | O(log(n)) | O(n) | Medium | 50 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Maximum Element | Push-O(1), Delete - O(n), Print - O(1) | Push - O(1), Delete - O(1), Print - O(1) | Easy | 20 | |||
| Balanced Brackets | O(n) | O(n) | Medium | 25 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Queue using Two Stacks | Enqueue - O(1), Dequeue - O(n), Print - O(n) | Enqueue - O(1), Dequeue - O(1), Print - O(1) | Medium | 30 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| QHEAP1 | Insert - O(log(n)), Delete - O(n), Print - O(1) | Insert - O(1), Delete - O(1), Print - O(1) | Easy | 25 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Spaceholder | O(1) | O(1) | Easy | 1 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Data Structures MCQ 1 | NA | NA | Hard | 5 | |||
| Data Structures MCQ 2 | NA | NA | Hard | 5 | |||
| Data Structures MCQ 3 | NA | NA | Hard | 5 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Contacts | Add - O(L), Find - O(L) | Add - O(L), Find - O(1) | Medium | 40 | L = Length of a contact name |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Spaceholder | O(1) | O(1) | Easy | 1 |
| # | Title | Solution | Time | Space | Difficulty | Points | Note |
|---|---|---|---|---|---|---|---|
| Leonardo's Prime Factors | O(1) | O(1) | Easy | 10 |