daily tracker

Ray (Red) vs Hayden (Green) vs Arthur (Blue)

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Daily Challenge - Day 165 (Started Dec 8, 2025)

🟢 Easy	🟡 Medium	🔴 Hard	📐 Project Euler (2/day)	🚀 NeetCode
Strong Password Checker II	Minimum Number of Days to Make m Bouquets	Maximum Score of a Node Sequence	Prime Frog Euler's Number	NeetCode Practice

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total growth over time

note: a 0.1 jitter is added to scores so lines don't overlap if we are tied

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📊 Category Breakdown

LeetCode	NeetCode	Project Euler

how to submit

1. go to your folder (eg. ray/leetcode)
2. add your solution file (.py, .js, .cpp etc)
3. Push to main.
4. the bot will update the graphs in ~30 seconds
5. yay!

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Click to view previous challenges

Day	Date	Easy	Medium	Hard	Euler
Day 165	2026-05-21	Strong Password Checker II	Minimum Number of Days to Make m Bouquets	Maximum Score of a Node Sequence	Prime Frog Euler's Number
Day 164	2026-05-20	Detect Capital	Check Knight Tour Configuration	Cherry Pickup	Rooms of Doom Lowest-cost Search
Day 163	2026-05-19	Second Largest Digit in a String	Maximum Area of a Piece of Cake After Horizontal and Vertical Cuts	Make Array Strictly Increasing	Stone Game II Modulo Summations
Day 162	2026-05-18	Remove Duplicates from Sorted Array	Count Number of Ways to Place Houses	Encrypt and Decrypt Strings	Bitwise-OR Operations on Random Integers Building a Tower
Day 161	2026-05-17	Flip Square Submatrix Vertically	Find Xor-Beauty of Array	Maximum Sum Queries	Swapping Counters Binomial Coefficients Divisible by 10
Day 160	2026-05-16	Smallest Divisible Digit Product I	Single Number II	Minimum Number of Days to Disconnect Island	Bounded Sequences Factorials Divisible by a Huge Integer
Day 159	2026-05-15	Implement Stack using Queues	Seat Reservation Manager	Maximize Grid Happiness	Firecracker 2011 Nines
Day 158	2026-05-14	Delete Characters to Make Fancy String	Sorting Three Groups	The Number of Good Subsets	Digital Root Clocks Numbers in Decimal Expansions
Day 157	2026-05-13	Find the Distance Value Between Two Arrays	Simplify Path	Split Message Based on Limit	Sliding Game The Mouse on the Moon
Day 156	2026-05-12	Maximum Number of Words Found in Sentences	Count Number of Homogenous Substrings	Maximum Sum of 3 Non-Overlapping Subarrays	Biclinic Integral Quadrilaterals Cyclic Paths on Sierpiński Graphs
Day 155	2026-05-11	Pass the Pillow	Minimum Bitwise OR From Grid	Second Minimum Time to Reach Destination	Integer Ladders Nim Square
Day 154	2026-05-10	Find the Highest Altitude	Binary Search Tree Iterator	Integer to English Words	Chip Defects An Amazing Prime-generating Automaton
Day 153	2026-05-09	Minimum Operations to Make Array Values Equal to K	Count Beautiful Splits in an Array	Minimum Number of Increments on Subarrays to Form a Target Array	Reflexive Position Paper-strip Game
Day 152	2026-05-08	Find the Maximum Divisibility Score	Combination Sum III	Count the Number of Ideal Arrays	Multiples with Small Digits Primonacci
Day 151	2026-05-07	Longest Even Odd Subarray With Threshold	Cinema Seat Allocation	Number Of Ways To Reconstruct A Tree	Nim Strong Achilles Numbers
Day 150	2026-05-06	Matrix Similarity After Cyclic Shifts	Find Kth Largest XOR Coordinate Value	Contain Virus	Three Similar Triangles Protein Folding
Day 149	2026-05-05	Binary Tree Tilt	Minimum Domino Rotations For Equal Row	Maximum Deletions on a String	Zeckendorf Representation Selective Amnesia
Day 148	2026-05-04	Adjacent Increasing Subarrays Detection I	Perfect Squares	Minimize Malware Spread	Lenticular Holes Angular Bisector and Tangent
Day 147	2026-05-03	Count Prefixes of a Given String	Smallest All-Ones Multiple	Maximum Number of Moves to Kill All Pawns	Pseudo-Fortunate Numbers Sum of Digits - Experience #23
Day 146	2026-05-02	Find Valid Emails	Capital Gain/Loss	Poor Pigs	Panaitopol Primes Pythagorean Polygons
Day 145	2026-05-01	Check if Two Chessboard Squares Have the Same Color	Loud and Rich	Maximum XOR of Subsequences	Eulerian Cycles Digital Signature
Day 144	2026-04-30	XOR Operation in an Array	Largest Values From Labels	Serialize and Deserialize Binary Tree	Quadtree Encoding (a Simple Compression Algorithm) An Enormous Factorial
Day 143	2026-04-29	Find Maximum Number of String Pairs	Word Search	Find Zombie Sessions	Pythagorean Odds Scoring Probabilities
Day 142	2026-04-28	Number of Unequal Triplets in Array	Find the Maximum Length of Valid Subsequence II	Rank Transform of a Matrix	Integer Sided Triangles with Integral Area/perimeter Ratio Steady Squares
Day 141	2026-04-27	Special Positions in a Binary Matrix	Sum Root to Leaf Numbers	Total Sum of Interaction Cost in Tree Groups	Pizza Toppings The Ackermann Function
Day 140	2026-04-26	Count Tested Devices After Test Operations	Distribute Coins in Binary Tree	Kth Smallest Instructions	Triangles with Integral Sides and an Integral Angle Ant and Seeds
Day 139	2026-04-25	Invert Binary Tree	Minimum Equal Sum of Two Arrays After Replacing Zeros	Reconstruct Itinerary	A Modified Collatz Sequence Linear Combinations of Semiprimes
Day 138	2026-04-24	Circular Sentence	Construct Uniform Parity Array II	Minimum Edge Weight Equilibrium Queries in a Tree	Balanced Sculptures Primitive Triangles
Day 137	2026-04-23	Compute Alternating Sum	Number of Enclaves	Minimum Operations to Equalize Subarrays	Sum of Squares Divisibility Multipliers
Day 136	2026-04-22	Minimum Pair Removal to Sort Array I	Mirror Reflection	Groups of Strings	Modular Cubes, Part 1 Modular Cubes, Part 2
Day 135	2026-04-21	Count Vowel Substrings of a String	Rotate Image	Frog Position After T Seconds	Polynomials with at Least One Integer Root Cutting Squares
Day 134	2026-04-20	Employees Earning More Than Their Managers	Plates Between Candles	Equal Sum Grid Partition II	Billionaire At Least Four Distinct Prime Factors Less Than 100
Day 133	2026-04-19	Split a String in Balanced Strings	Sum of Distances	Most Common Course Pairs	Binary Circles Pseudo Square Root
Day 132	2026-04-18	Maximum Number of Pairs in Array	Maximum Value after Insertion	Shortest Distance After Road Addition Queries II	An Engineers' Dream Come True Triangle Centres
Day 131	2026-04-17	Triangle Judgement	The Number of the Smallest Unoccupied Chair	Arithmetic Slices II - Subsequence	Pivotal Square Sums Mountain Range
Day 130	2026-04-16	Number of Beautiful Pairs	Sum of Two Integers	Cat and Mouse	Reachable Numbers Stone Game
Day 129	2026-04-15	Count Common Words With One Occurrence	Minesweeper	Patching Array	Angular Bisectors A Lagged Fibonacci Sequence
Day 128	2026-04-14	The Latest Login in 2020	Minimum Operations to Make Array Equal II	Equal Rational Numbers	Rounded Square Roots Tatami-Free Rooms
Day 127	2026-04-13	Max Consecutive Ones	Minimum Number of Flips to Make the Binary String Alternating	Palindromic Path Queries in a Tree	Tidying Up A Sums of Digit Factorials
Day 126	2026-04-12	Transform Array by Parity	Last Moment Before All Ants Fall Out of a Plank	Maximum Score Using Exactly K Pairs	Cardano Triplets Convex Holes
Day 125	2026-04-11	Cells in a Range on an Excel Sheet	Longest Balanced Subarray I	Minimum Money Required Before Transactions	Problem 249 Problem 250
Day 124	2026-04-10	Check If All 1's Are at Least Length K Places Away	Find Books with Polarized Opinions	Painting the Walls	Squares Under a Hyperbola Euler's Totient Function Equals 13!
Day 123	2026-04-09	Subtree of Another Tree	Minimum Moves to Spread Stones Over Grid	Minimum Cost to Reach Destination in Time	Problem 245 Problem 246
Day 122	2026-04-08	Teemo Attacking	Minimum Sideway Jumps	Erect the Fence	Resilience Sliders
Day 121	2026-04-07	Greatest English Letter in Upper and Lower Case	Flatten Nested List Iterator	Sum of Distances in Tree	Perfection Quotients Odd Triplets
Day 120	2026-04-06	Power of Two	Max Chunks To Make Sorted	Fancy Sequence	Twenty-two Foolish Primes Top Dice
Day 119	2026-04-05	Majority Frequency Characters	Rectangle Area	Split the Array to Make Coprime Products	Tours on a $4 imes N$ Playing Board Infinite String Tour
Day 118	2026-04-04	Binary Tree Inorder Traversal	Minimum Discards to Balance Inventory	Max Dot Product of Two Subsequences	An Arithmetic Geometric Sequence Luxury Hampers
Day 117	2026-04-03	GCD of Odd and Even Sums	Find Elements in a Contaminated Binary Tree	Tag Validator	Lattice Points on a Circle Semidivisible Numbers
Day 116	2026-04-02	Time Needed to Buy Tickets	Time Needed to Rearrange a Binary String	Find K-th Smallest Pair Distance	Prime Factorisation of Binomial Coefficients The Race
Day 115	2026-04-01	Number of Common Factors	Number of Times Binary String Is Prefix-Aligned	Maximum Product of Subsequences With an Alternating Sum Equal to K	Four Representations Using Squares Fibonacci Words
Day 114	2026-03-31	Image Smoother	Search a 2D Matrix	Length of Longest V-Shaped Diagonal Segment	The Chase Minkowski Sums
Day 113	2026-03-30	Ugly Number	Can I Win	Greatest Common Divisor Traversal	Tribonacci Non-divisors A Scoop of Blancmange
Day 112	2026-03-29	Determine if Two Events Have Conflict	Implement Rand10() Using Rand7()	Earliest Possible Day of Full Bloom	Almost Right-angled Triangles I Almost Right-angled Triangles II
Day 111	2026-03-28	Reverse Bits	Find All Groups of Farmland	Count Good Subarrays	Alexandrian Integers Sphere Packing
Day 110	2026-03-27	Prime Number of Set Bits in Binary Representation	Find All Lonely Numbers in the Array	Largest Component Size by Common Factor	Skew-cost Coding Heighway Dragon
Day 109	2026-03-26	Minimum Changes To Make Alternating Binary String	Maximum Score After Binary Swaps	Minimum Obstacle Removal to Reach Corner	Problem 217 Problem 218
Day 108	2026-03-25	Split the Array	Join Two Arrays by ID	Number of Possible Sets of Closing Branches	Crack-free Walls The Primality of $2n^2 - 1$
Day 107	2026-03-24	X of a Kind in a Deck of Cards	Maximum Product After K Increments	Number of ZigZag Arrays I	Flea Circus Totient Chains
Day 106	2026-03-23	Find Subsequence of Length K With the Largest Sum	Count Subarrays With Cost Less Than or Equal to K	Course Schedule III	Divisor Square Sum Combined Volume of Cuboids
Day 105	2026-03-22	Number of Senior Citizens	Minimized Maximum of Products Distributed to Any Store	Kth Ancestor of a Tree Node	Circular Logic Obtuse Angled Triangles
Day 104	2026-03-21	Defanging an IP Address	XOR Queries of a Subarray	Count Vowels Permutation	Integer Partition Equations Robot Walks
Day 103	2026-03-20	Jewels and Stones	Call Function with Custom Context	Reaching Points	Dice Game Concealed Square
Day 102	2026-03-19	Toggle Light Bulbs	Maximum Weighted K-Edge Path	Minimum Cost to Equalize Array	Squarefree Binomial Coefficients Generalised Hamming Numbers
Day 101	2026-03-18	Split With Minimum Sum	Maximum Points Inside the Square	Minimum Swaps To Make Sequences Increasing	Subsets with a Unique Sum Laserbeam
Day 100	2026-03-17	Find the Town Judge	Find the Value of the Partition	Concatenated Words	Iterative Circle Packing Prime-proof Squbes
Day 99	2026-03-16	Permutation Difference between Two Strings	Maximum Element After Decreasing and Rearranging	Regular Expression Matching	A Recursively Defined Sequence Ambiguous Numbers
Day 98	2026-03-15	Find Missing Elements	Finding Pairs With a Certain Sum	Minimum Initial Energy to Finish Tasks	$60$-degree Triangle Inscribed Circles Prime Triplets
Day 97	2026-03-14	Rearrange Spaces Between Words	Find Mirror Score of a String	String Transformation	Squarefree Numbers Coloured Configurations
Day 96	2026-03-13	Drop Duplicate Rows	Unique Paths II	Falling Squares	Prize Strings Best Approximations
Day 95	2026-03-12	Check if Binary String Has at Most One Segment of Ones	Longest Palindrome After Substring Concatenation I	Find the K-th Character in String Game II	Tri-colouring a Triangular Grid Maximising a Weighted Product
Day 94	2026-03-11	Find All K-Distant Indices in an Array	Next Greater Element II	Minimum Cost to Merge Stones	Semiprimes Hyperexponentiation
Day 93	2026-03-10	Check Balanced String	Minimum Operations to Make a Uni-Value Grid	Minimum Time to Complete All Tasks	Number Mind Connectedness of a Network
Day 92	2026-03-09	Find Missing and Repeated Values	Longest Subarray With Maximum Bitwise AND	Smallest Palindromic Rearrangement II	Maximum Product of Parts Triangles Containing the Origin
Day 91	2026-03-08	Divisor Game	Maximum Product of Two Integers With No Common Bits	Process String with Special Operations II	Problem 181 Problem 182
Day 90	2026-03-07	Determine Color of a Chessboard Square	Solving Questions With Brainpower	Kth Smallest Path XOR Sum	Consecutive Positive Divisors Golden Triplets
Day 89	2026-03-06	Fix Names in a Table	Partition Array into Disjoint Intervals	Minimum Increments for Target Multiples in an Array	Integer Angled Quadrilaterals Step Numbers
Day 88	2026-03-05	Find Users With Valid E-Mails	Find Subtree Sizes After Changes	Building Boxes	Fractions and Sum of Powers of Two Common Cathetus Right-angled Triangles
Day 87	2026-03-04	Shuffle String	Count of Substrings Containing Every Vowel and K Consonants II	GCD Sort of an Array	Hollow Square Laminae I Hollow Square Laminae II
Day 86	2026-03-03	Longest Harmonious Subsequence	Lexicographically Smallest String After Applying Operations	Design Cancellable Function	Square Sum of the Digital Squares Few Repeated Digits
Day 85	2026-03-02	Hexadecimal and Hexatrigesimal Conversion	Maximum Number of Events That Can Be Attended	Sum of Imbalance Numbers of All Subarrays	Sums of Powers of Two Pandigital Concatenating Products
Day 84	2026-03-01	Vowel-Consonant Score	Design Front Middle Back Queue	Find the Shortest Superstring	Investigating Ulam Sequences Number Rotations
Day 83	2026-02-28	To Be Or Not To Be	Maximum Sum With at Most K Elements	Count The Repetitions	Intersections Criss Cross
Day 82	2026-02-27	Find the Number of Winning Players	Minimum Moves to Make Array Complementary	Minimum Time to Finish the Race	Cross-hatched Triangles Three Consecutive Digital Sum Limit
Day 81	2026-02-26	Remove Palindromic Subsequences	Shortest Uncommon Substring in an Array	Minimum Partition Score	Triominoes Hexadecimal Numbers
Day 80	2026-02-25	Isomorphic Strings	Minimum Cost to Make Two Binary Strings Equal	Minimum Inversion Count in Subarrays of Fixed Length	Digital Root Sums of Factorisations Factorial Trailing Digits
Day 79	2026-02-24	Number of Different Integers in a String	Champagne Tower	Maximize Sum of Weights after Edge Removals	Base-10 Diophantine Reciprocal Lexicographical Neighbours
Day 78	2026-02-23	Equal Score Substrings	Find the Most Common Response	Department Top Three Salaries	Counting Capacitor Circuits Counting Digits
Day 77	2026-02-22	Merge Two Binary Trees	Combination Sum II	Longest Duplicate Substring	Investigating Gaussian Integers Exploring Pascal's Pyramid
Day 76	2026-02-21	Maximum Length Substring With Two Occurrences	Count Number of Texts	IPO	A Preference for A5 Sums of Square Reciprocals
Day 75	2026-02-20	Minimum Number of Pushes to Type Word I	First Element with Unique Frequency	Paint House III	Maximum-sum Subsequence Sub-triangle Sums
Day 74	2026-02-19	Duplicate Emails	Koko Eating Bananas	Maximize Alternating Sum Using Swaps	Rectangles in Cross-hatched Grids Exploring Pascal's Triangle
Day 73	2026-02-18	Check if Matrix Is X-Matrix	Wiggle Sort II	Minimum Number of Refueling Stops	Problem 145 Problem 146
Day 72	2026-02-17	Is Object Empty	Populating Next Right Pointers in Each Node II	Stone Game IV	Torricelli Triangles Laser Beam Reflections
Day 71	2026-02-16	Sum of Elements With Frequency Divisible by K	Shortest and Lexicographically Smallest Beautiful String	Maximum Number of Non-overlapping Palindrome Substrings	Square Progressive Numbers Perfect Square Collection
Day 70	2026-02-15	Count the Digits That Divide a Number	Path In Zigzag Labelled Binary Tree	Maximum Good Subtree Score	Pythagorean Tiles Modified Fibonacci Golden Nuggets
Day 69	2026-02-14	Most Frequent Even Element	Ugly Number III	Minimum Amount of Damage Dealt to Bob	Fibonacci Golden Nuggets Special Isosceles Triangles
Day 68	2026-02-13	Subtract the Product and Sum of Digits of an Integer	Print FooBar Alternately	Candy	Same Differences Singleton Difference
Day 67	2026-02-12	Alternating Groups I	Insufficient Nodes in Root to Leaf Paths	Minimum Cost to Cut a Stick	Repunit Nonfactors Prime Pair Connection
Day 66	2026-02-11	Binary Gap	Airplane Seat Assignment Probability	Find Sum of Array Product of Magical Sequences	Prime Cube Partnership Large Repunit Factors
Day 65	2026-02-10	Matrix Diagonal Sum	Generate Binary Strings Without Adjacent Zeros	Online Majority Element In Subarray	Repunit Divisibility Composites with Prime Repunit Property
Day 64	2026-02-09	Maximum Units on a Truck	Lexicographically Minimum String After Removing Stars	Shortest Path to Get All Keys	abc-hits Hexagonal Tile Differences
Day 63	2026-02-08	Range Sum of BST	Exam Room	Russian Doll Envelopes	Palindromic Sums Cuboid Layers
Day 62	2026-02-07	Valid Perfect Square	Identify the Largest Outlier in an Array	Sum of Scores of Built Strings	Prime Square Remainders Ordered Radicals
Day 61	2026-02-06	Number Complement	Eliminate Maximum Number of Monsters	N-Queens II	Disc Game Prize Fund Efficient Exponentiation
Day 60	2026-02-05	Check if Any Element Has Prime Frequency	Circular Array Loop	Lexicographically Smallest Generated String	Digit Power Sum Square Remainders
Day 59	2026-02-04	Sum of All Subset XOR Totals	Magical String	Check If Digits Are Equal in String After Operations II	Red, Green, and Blue Tiles Pandigital Prime Sets
Day 58	2026-02-03	Count Good Triplets	Count the Hidden Sequences	Redundant Connection II	Counting Block Combinations II Red, Green or Blue Tiles
Day 57	2026-02-02	Find the Longest Balanced Substring of a Binary String	Insert Greatest Common Divisors in Linked List	Maximize the Number of Target Nodes After Connecting Trees II	Non-bouncy Numbers Counting Block Combinations I
Day 56	2026-02-01	Find The Least Frequent Digit	The kth Factor of n	Shortest Path in a Weighted Tree	Primes with Runs Bouncy Numbers
Day 55	2026-01-31	Climbing Stairs	High-Access Employees	Find the Count of Good Integers	Darts Diophantine Reciprocals II
Day 54	2026-01-30	Design an Ordered Stream	Longest Palindromic Subsequence	Minimum Distance to Type a Word Using Two Fingers	Minimal Network Diophantine Reciprocals I
Day 53	2026-01-29	Final Prices With a Special Discount in a Shop	Substring XOR Queries	Maximum Total Beauty of the Gardens	Special Subset Sums: Testing Special Subset Sums: Meta-testing
Day 52	2026-01-28	Degree of an Array	Minimum Number of Food Buckets to Feed the Hamsters	Count Pairs With XOR in a Range	Special Subset Sums: Optimum Pandigital Fibonacci Ends
Day 51	2026-01-27	Absolute Difference Between Maximum and Minimum K Elements	Score of Parentheses	Analyze Organization Hierarchy	Optimum Polynomial Triangle Containment
Day 50	2026-01-26	Find Nearest Point That Has the Same X or Y Coordinate	Find the Longest Substring Containing Vowels in Even Counts	Finding MK Average	Largest Exponential Arranged Probability
Day 49	2026-01-25	Fibonacci Number	Rearrange Array Elements by Sign	Valid Number	Large Non-Mersenne Prime Anagramic Squares
Day 48	2026-01-24	Find Special Substring of Length K	Maximum Product of the Length of Two Palindromic Subsequences	Find Beautiful Indices in the Given Array II	Amicable Chains Su Doku
Day 47	2026-01-23	N-th Tribonacci Number	Subsets	Minimum Operations to Equalize Binary String	Arithmetic Expressions Almost Equilateral Triangles
Day 46	2026-01-22	Sort By	Find the Longest Semi-Repetitive Substring	Check if an Original String Exists Given Two Encoded Strings	Right Triangles with Integer Coordinates Square Digit Chains
Day 45	2026-01-21	Employees Whose Manager Left the Company	Unique Length-3 Palindromic Subsequences	Maximize Cyclic Partition Score	Roman Numerals Cube Digit Pairs
Day 44	2026-01-20	Move Zeroes	Maximum Number of Non-Overlapping Subarrays With Sum Equals Target	Maximum Candies You Can Get from Boxes	Problem 87 Problem 88
Day 43	2026-01-19	Account Balance After Rounded Purchase	Cousins in Binary Tree II	Minimum Possible Integer After at Most K Adjacent Swaps On Digits	Counting Rectangles Cuboid Route
Day 42	2026-01-18	Slowest Key	Remove Nth Node From End of List	Permutation Sequence	Path Sum: Four Ways Monopoly Odds
Day 41	2026-01-17	Binary Search	Minimum Number of Valid Strings to Form Target I	Find the Minimum Area to Cover All Ones II	Path Sum: Two Ways Path Sum: Three Ways
Day 40	2026-01-16	Happy Number	Implement Magic Dictionary	Make Array Empty	Passcode Derivation Square Root Digital Expansion
Day 39	2026-01-15	Remove Outermost Parentheses	Find The First Player to win K Games in a Row	Shortest Subarray with Sum at Least K	Prime Summations Coin Partitions
Day 38	2026-01-14	Check If String Is a Prefix of Array	Most Profitable Path in a Tree	Minimum Cost to Make at Least One Valid Path in a Grid	Singular Integer Right Triangles Counting Summations
Day 37	2026-01-13	Find Mode in Binary Search Tree	Alert Using Same Key-Card Three or More Times in a One Hour Period	Shortest Impossible Sequence of Rolls	Counting Fractions in a Range Digit Factorial Chains
Day 36	2026-01-12	Reverse Only Letters	Minimum Cost to Make Arrays Identical	Total Characters in String After Transformations II	Ordered Fractions Counting Fractions
Day 35	2026-01-11	Find Products with Valid Serial Numbers	Count Zero Request Servers	Basic Calculator IV	Totient Maximum Totient Permutation
Day 34	2026-01-10	Count Negative Numbers in a Sorted Matrix	Stone Game VII	Maximum Profit from Valid Topological Order in DAG	Maximum Path Sum II Magic 5-gon Ring
Day 33	2026-01-09	Sort Array By Parity II	Maximize Score of Numbers in Ranges	Dice Roll Simulation	Convergents of $e$ Diophantine Equation
Day 32	2026-01-08	Find Target Indices After Sorting Array	Minimum Number of Coins to be Added	Maximize the Distance Between Points on a Square	Powerful Digit Counts Odd Period Square Roots
Day 31	2026-01-07	Largest Even Number	Beautiful Towers II	Maximum Number of K-Divisible Components	Cyclical Figurate Numbers Cubic Permutations
Day 30	2026-01-06	Count Prefix and Suffix Pairs I	Taking Maximum Energy From the Mystic Dungeon	Number of Increasing Paths in a Grid	XOR Decryption Prime Pair Sets
Day 29	2026-01-05	Buddy Strings	Check if Grid can be Cut into Sections	Find All People With Secret	Square Root Convergents Spiral Primes
Day 28	2026-01-04	Swap Sex of Employees	Count Sorted Vowel Strings	Zuma Game	Lychrel Numbers Powerful Digit Sum
Day 27	2026-01-03	Kth Missing Positive Number	Maximum Length of Subarray With Positive Product	Number of Beautiful Integers in the Range	Combinatoric Selections Poker Hands
Day 26	2026-01-02	Goat Latin	Minimum Elements to Add to Form a Given Sum	Longest Subsequence Repeated k Times	Prime Digit Replacements Permuted Multiples
Day 25	2026-01-01	Latest Time by Replacing Hidden Digits	Non-decreasing Array	Length of the Longest Increasing Path	Problem 49 Problem 50
Day 24	2025-12-31	Decode XORed Array	Apply Operations to Make Sum of Array Greater Than or Equal to k	Cat and Mouse II	Distinct Primes Factors Self Powers
Day 23	2025-12-30	Arranging Coins	Minimum Deletion Cost to Make All Characters Equal	Distinct Subsequences	Triangular, Pentagonal, and Hexagonal Goldbach's Other Conjecture
Day 22	2025-12-29	Maximum Sum With Exactly K Elements	Difference Between Ones and Zeros in Row and Column	Number of Flowers in Full Bloom	Problem 43 Problem 44
Day 21	2025-12-28	Intersection of Two Arrays	Maximum Absolute Sum of Any Subarray	Count K-Reducible Numbers Less Than N	Pandigital Prime Coded Triangle Numbers
Day 20	2025-12-27	Two Sum IV - Input is a BST	Minimum Number of Operations to Have Distinct Elements	Max Value of Equation	Integer Right Triangles Champernowne's Constant
Day 19	2025-12-26	Check if The Number is Fascinating	Matchsticks to Square	Shortest Matching Substring	Truncatable Primes Pandigital Multiples
Day 18	2025-12-25	Binary Prefix Divisible By 5	Maximum Ice Cream Bars	Count the Number of Houses at a Certain Distance II	Circular Primes Double-base Palindromes
Day 17	2025-12-24	Rename Columns	Rotting Oranges	Find the Occurrence of First Almost Equal Substring	Digit Cancelling Fractions Digit Factorials
Day 16	2025-12-23	Word Pattern	Construct the Longest New String	Longest Happy Prefix	Coin Sums Pandigital Products
Day 15	2025-12-22	Longer Contiguous Segments of Ones than Zeros	Lexicographically Smallest Equivalent String	Count of Integers	Distinct Powers Digit Fifth Powers
Day 14	2025-12-21	Leaf-Similar Trees	Count and Say	Count Subarrays With Score Less Than K	Quadratic Primes Number Spiral Diagonals
Day 13	2025-12-20	Maximum 69 Number	Find Unique Binary String	Find the Number of Ways to Place People II	$1000$-digit Fibonacci Number Reciprocal Cycles
Day 12	2025-12-19	Check if Number Has Equal Digit Count and Digit Value	House Robber III	Count Connected Components in LCM Graph	Non-Abundant Sums Lexicographic Permutations
Day 11	2025-12-18	Count Distinct Numbers on Board	Find the Largest Area of Square Inside Two Rectangles	Minimum Number of Valid Strings to Form Target II	Amicable Numbers Names Scores
Day 10	2025-12-17	Project Employees I	Longest Mountain in Array	Partition Array for Maximum XOR and AND	Counting Sundays Factorial Digit Sum
Day 9	2025-12-16	Minimum Operations to Collect Elements	Employee Importance	Minimize Deviation in Array	Number Letter Counts Maximum Path Sum I
Day 8	2025-12-15	Number of Bit Changes to Make Two Integers Equal	Digit Operations to Make Two Integers Equal	Merge Operations for Minimum Travel Time	Lattice Paths Power Digit Sum
Day 7	2025-12-14	Consecutive Characters	Insert Interval	Count Distinct Subarrays Divisible by K in Sorted Array	Large Sum Longest Collatz Sequence

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