Problems

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Total results29,419 problems

Garbled Email (Small)
Medium6
Dynamic programming, Trie
No attempts yet
Time limit
30s
Memory limit
512 MB
Judgeable
Fair and Square (Large 1)
Medium6
Math, Brute force+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Treasure Chests (Small)
Medium6
Backtracking, DFS+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Professor Normal's Marble Game
Medium6
Simulation, Queue+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Zombie Smash (Large)
Medium6
Dynamic programming, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Xeno-archaeology (Small)
Medium6
Brute force, Math+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Shifting Paths (Small)
Medium6
Simulation, Graph
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Quality Food
Medium6
Binary search, Greedy+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Swinging Wild (Small)
Medium6
Graph, Dynamic programming
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Box Factory (Small)
Medium6
Dynamic programming
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Safety in Numbers (Small)
Medium6
Binary search, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Shoot the Target (Small1)
Medium6
Geometry, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Shoot the Target
Medium6
Geometry, Math
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Street Tree Props (Small)
Medium6
Backtracking, Sorting
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Sunlight Hours (Small)
Medium6
Geometry, Binary search
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Antenna repair (Large)
Medium6
Combinatorics, Sorting+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Wildcard (Small)
Medium6
String matching, Brute force+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Closet Room (Small)
Medium6
Backtracking, Brute force+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Infinite Garden (Large)
Medium6
BFS, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Rains Over Atlantis (Small)
Medium6
Simulation, Heap+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Google Royale (Small)
Medium6
Dynamic programming, Probability+1
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Shortest Straight
Medium6
Greedy, Binary search+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Airport Walkways (Large)
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Spinning Blade (Large)
Medium6
Prefix sum, Brute force
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
A.I. War (Small)
Medium6
Shortest path, BFS+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
A.I. War (Large)
Medium6
BFS, Shortest path+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Revenge of the Hot Dogs (Small)
Medium6
Binary search, Greedy+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
House of Kittens (Small)
Medium6
Brute force, Graph
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Pseudominion (Small)
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Parcel Posts
Medium6
Greedy, Array
No attempts yet
Time limit
20s
Memory limit
1024 MB
Judgeable
Roads on the Battlefield
Medium6
Graph, Union-find+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Radio Receiver (Small)
Medium6
Binary search, Intervals+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Radio Receiver
Medium6
Binary search, Intervals+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
De-RNG-ed (Small)
Medium6
Brute force, Number theory+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Elegant Diamond (Small)
Medium6
Brute force, Matrix
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Elegant Diamond
Medium6
Brute force, Implementation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
World Cup 2010 (Small)
Medium6
Dynamic programming, Tree
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Make It Smooth (Small)
Medium6
Dynamic programming, Shortest path+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Qualification Round (Small)
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Qualification Round (Large)
Medium6
Greedy, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Polygraph (Small)
Medium6
Brute force, Simulation+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
EZ-Sokoban
Medium6
BFS, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Alphabetomials (Small)
Medium6
Dynamic programming, Math+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Football Team Photo
Medium6
Graph, Sorting+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Football Team (Large)
Medium6
Graph, Greedy+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
All Your Base (Small)
Medium6
Greedy, Math+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Center of Mass of a Firefly Swarm
Medium6
Math, Geometry+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
The Next Number (Large)
Medium6
Combinatorics, Greedy+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Multi-base happy numbers
Medium6
Math, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Ping Pong Balls (Large)
Medium6
Graph, Implementation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Mine Layer (Small)
Medium6
Brute force, Backtracking+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Triangle Transformation
Medium6
Geometry, Math+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Rainbow Trees
Medium6
Dynamic programming, Tree+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Mixing Bowls (Small)
Medium6
Tree, DFS+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
King (Small)
Medium6
Game theory, DFS+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Modern Art Plagiarism
Medium6
Tree, DFS+1
No attempts yet
Time limit
50s
Memory limit
512 MB
Judgeable
Igra
Medium6
Greedy, String+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Endless Knight (Small)
Medium6
Dynamic programming, Combinatorics
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Triangle Areas
Medium6
Geometry, Math+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
PermRLE (Small)
Medium6
Brute force, Sorting+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Ugly Numbers (Large)
Medium6
Dynamic programming, Number theory+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Increasing Speed Limits
Medium6
Dynamic programming, Sorting+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Crop Triangles (Large)
Medium6
Math, Combinatorics+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Number Sets
Medium6
Union-find, Number theory+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Number Sets (Large)
Medium6
Union-find, Number theory+2
No attempts yet
Time limit
50s
Memory limit
512 MB
Judgeable
Last three digits of (3 + √5)^n
Medium6
Math, Number theory+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Pat Pat
Medium6
Segment tree, Array
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Mixture (Small)
Medium6
Geometry, Brute force+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Stacking Pancakes
Medium6
BFS, Brute force+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Swap
Medium6
Greedy, Tree+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Stone Bridge
Medium6
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Don't be late
Medium6
Shortest path, Graph+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Junha at the Internet Lounge
Medium6
Sorting, Heap+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Multiplication Game
Medium6
Dynamic programming, Number theory
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Republic of Inhanica
Medium6
Tree, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Rigging the Draw
Medium6
Graph, Simulation+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Gennady is smart
Medium6
Prefix sum, Matrix+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Palinilap
Medium6
String, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Binary string restoration
Medium6
String, Greedy+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
New Tree
Medium6
Geometry, Brute force
No attempts yet
Time limit
0.2s
Memory limit
1024 MB
Judgeable
Universities
Medium6
Tree, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lexicographic Sorting
Medium6
Sorting, String+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Three-Way Junction
Medium6
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
London Underground
Medium6
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Fried Soboro Buns
Medium6
Binary search, Sorting+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Double Major
Medium6
Graph, Union-find+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Card Fusion Event
Medium6
Intervals, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
A Scary Part-Time Job
Medium6
Stack, Greedy
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Stick Game
Medium6
Game theory, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Jumping Minho
Medium6
Dynamic programming, Number theory+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Placing Two Snakes
Medium6
Math, Combinatorics+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Mutalisk
Medium6
Dynamic programming, Brute force
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Playlist
Medium6
Dynamic programming, Combinatorics+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Royal Decree
Medium6
Graph, Shortest path+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Painting blocks
Medium6
Combinatorics, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Minimum weight spread for strong connectivity
Medium6
Graph, Sorting+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Stone Groups
Medium6
BFS, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Path Game
Medium6
Dynamic programming, Graph+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Equivalent Strings
Medium6
Divide and conquer, String+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Colorful Village
Medium6
Segment tree, Bit manipulation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Garbled Email (Small)Split the received string into dictionary words with changed letters at least 5 apart and as few changes as possible.	Medium6	Dynamic programmingTrie	No attempts yet	30s	512 MB	Judgeable
Fair and Square (Large 1)Count the integers in each interval [A, B] that are palindromes and the square of a palindrome.	Medium6	MathBrute force+1	No attempts yet	5s	512 MB	Judgeable
Treasure Chests (Small)Open all N chests in the lexicographically smallest valid order using keys found inside chests, or report IMPOSSIBLE.	Medium6	BacktrackingDFS+2	No attempts yet	5s	512 MB	Judgeable
Professor Normal's Marble GameChildren on a grid repeatedly drop out when short on marbles, then survivors pass 12 marbles to neighbors; count the exchanges or the children who play forever.	Medium6	SimulationQueue+1	No attempts yet	5s	512 MB	Judgeable
Zombie Smash (Large)Plan a route from the origin that smashes the most time-windowed zombies given Chebyshev travel time and a 750 ms weapon recharge.	Medium6	Dynamic programmingSorting+1	No attempts yet	5s	512 MB	Judgeable
Xeno-archaeology (Small)Given colored tiles from an infinite square ring pattern, find the pattern center that fits all tiles with the stated tie breaks.	Medium6	Brute forceMath+1	No attempts yet	5s	512 MB	Judgeable
Shifting Paths (Small)Count the steps of a walk that alternates between two outgoing edges at each revisit, or report Infinity when clearing N is never reached.	Medium6	SimulationGraph	No attempts yet	5s	512 MB	Judgeable
Quality FoodGiven meal prices, staleness limits, a delivery fee, and a budget, maximize the number of consecutive days from day 1 with one quality meal each day.	Medium6	Binary searchGreedy+1	No attempts yet	5s	512 MB	Judgeable
Swinging Wild (Small)Decide whether a chain of vine swings, each limited by grip distance and vine length, reaches the far ledge.	Medium6	GraphDynamic programming	No attempts yet	5s	512 MB	Judgeable
Box Factory (Small)Match boxes and toys from two run-length encoded lines in order to maximize the number of equal-type pairs.	Medium6	Dynamic programming	No attempts yet	5s	512 MB	Judgeable
Safety in Numbers (Small)Each contestant needs the smallest audience vote share that keeps them from ever finishing as the single lowest scorer.	Medium6	Binary searchMath	No attempts yet	5s	512 MB	Judgeable
Shoot the Target (Small1)Given a slanted segment above the x-axis, find the point on the x-axis that sees the segment under the largest angle and print that angle in degrees.	Medium6	GeometryMath	No attempts yet	5s	512 MB	Judgeable
Shoot the TargetPick the ground point on the x-axis that makes the given segment look widest and output that largest angle in degrees.	Medium6	GeometryMath	No attempts yet	5s	512 MB	Judgeable
Street Tree Props (Small)Each of up to 10 trees needs one stick of strength B or two sticks summing to B, using the smallest total strength.	Medium6	BacktrackingSorting	No attempts yet	5s	512 MB	Judgeable
Sunlight Hours (Small)Compute the share of building height that gets at least H hours of direct sun as the sun travels a semicircular path past blocking buildings.	Medium6	GeometryBinary search	No attempts yet	5s	512 MB	Judgeable
Antenna repair (Large)Arrange the given rod lengths on equally spaced rays around one point to maximize the sum of neighboring triangle areas.	Medium6	CombinatoricsSorting+2	No attempts yet	5s	512 MB	Judgeable
Wildcard (Small)Given two lowercase names, output the shortest wildcard pattern of letters and stars that matches the first name but not the second.	Medium6	String matchingBrute force+1	No attempts yet	5s	512 MB	Judgeable
Closet Room (Small)Place the maximum number of 2-cell closets with fixed door orientations on a grid with pillars so every door tile stays free and reachable from the entrance.	Medium6	BacktrackingBrute force+1	No attempts yet	5s	512 MB	Judgeable
Infinite Garden (Large)Compute the shortest axis-aligned route between two even-coordinate points in the maze drawn by the tape-driven robot without crossing its walls.	Medium6	BFSSimulation+1	No attempts yet	5s	512 MB	Judgeable
Rains Over Atlantis (Small)Simulate daily erosion on a height grid where trapped rainwater sets each cell water level and each outflow drop decides the height loss.	Medium6	SimulationHeap+1	No attempts yet	5s	512 MB	Judgeable
Google Royale (Small)Compute the best possible chance of growing A dollars to V dollars with capped doubling bets and report the largest opening bet that reaches it.	Medium6	Dynamic programmingProbability+1	No attempts yet	10s	512 MB	Judgeable
Shortest StraightPartition each hand of cards into consecutive runs covering every card so the shortest run is as long as possible.	Medium6	GreedyBinary search+1	No attempts yet	5s	512 MB	Judgeable
Airport Walkways (Large)Allocate up to t seconds of running between walkway and plain corridor segments to reach point X in minimum time.	Medium6	GreedySorting+1	No attempts yet	5s	512 MB	Judgeable
Spinning Blade (Large)Find the largest K by K square, with its four corner cells removed, whose cell masses balance exactly about the square center.	Medium6	Prefix sumBrute force	No attempts yet	5s	512 MB	Judgeable
A.I. War (Small)Starting from planet 0, conquer the fewest planets that threaten planet 1, preferring the choice that threatens the most planets, and output both counts.	Medium6	Shortest pathBFS+1	No attempts yet	5s	512 MB	Judgeable
A.I. War (Large)Find the smallest connected set of planets from planet 0 that borders planet 1, breaking ties by the largest border, and report both counts.	Medium6	BFSShortest path+1	No attempts yet	5s	512 MB	Judgeable
Revenge of the Hot Dogs (Small)Vendors on a line move at speed 1 and must end at least D apart, so find the smallest time that allows such positions.	Medium6	Binary searchGreedy+1	No attempts yet	5s	512 MB	Judgeable
House of Kittens (Small)Color the N polygon vertices with as many flavors as possible so every room touches each flavor, breaking ties by lexicographic order.	Medium6	Brute forceGraph	No attempts yet	5s	512 MB	Judgeable
Pseudominion (Small)Choose the order to play hand and deck cards so draws and extra turns produce the largest total score before turns run out.	Medium6	GreedySorting+1	No attempts yet	5s	512 MB	Judgeable
Parcel PostsSplit the elevation array into the most contiguous parcels so each parcel contains a triple whose middle value is strictly above or below both outer values.	Medium6	GreedyArray	No attempts yet	20s	1024 MB	Judgeable
Roads on the BattlefieldFor each test case, find the fewest new roads that allow a closed tour starting at one city and using every road exactly once.	Medium6	GraphUnion-find+1	No attempts yet	5s	512 MB	Judgeable
Radio Receiver (Small)Choose a walking path at speed at most one so every timed message on a line is within the smallest possible reception distance.	Medium6	Binary searchIntervals+1	No attempts yet	5s	512 MB	Judgeable
Radio ReceiverFind the smallest radius D that lets a person moving at speed one stay within D of each broadcast at its sending time.	Medium6	Binary searchIntervals+1	No attempts yet	5s	512 MB	Judgeable
De-RNG-ed (Small)Print the forced next term of K consecutive outputs from a linear generator modulo an unknown prime up to 10^D, or report that it is unknown.	Medium6	Brute forceNumber theory+1	No attempts yet	5s	512 MB	Judgeable
Elegant Diamond (Small)You embed the given digit diamond in a larger diamond with horizontal and vertical symmetry and add as few digits as possible.	Medium6	Brute forceMatrix	No attempts yet	5s	512 MB	Judgeable
Elegant DiamondEmbed the given digit diamond into a larger diamond symmetric about both axes with the fewest added digits.	Medium6	Brute forceImplementation+1	No attempts yet	5s	512 MB	Judgeable
World Cup 2010 (Small)Buy the cheapest set of knockout match tickets so each team misses at most its allowed number of games whatever the results.	Medium6	Dynamic programmingTree	No attempts yet	5s	512 MB	Judgeable
Make It Smooth (Small)Change, delete, or insert pixels at given costs so every pair of neighbors differs by at most M for the lowest total cost.	Medium6	Dynamic programmingShortest path+1	No attempts yet	5s	512 MB	Judgeable
Qualification Round (Small)Given how many contestants solved each of P problems, find the maximum possible number who solved at least C distinct problems.	Medium6	GreedySorting+1	No attempts yet	5s	512 MB	Judgeable
Qualification Round (Large)Given how many contestants solved each of P problems, find the maximum number who could have solved at least C distinct problems.	Medium6	GreedySorting+1	No attempts yet	5s	512 MB	Judgeable
Polygraph (Small)With at most 10 people, decide for each whether every satisfying assignment of truth-teller and liar types forces Truthtown, Liarville, or leaves it undecided.	Medium6	Brute forceSimulation+2	No attempts yet	5s	512 MB	Judgeable
EZ-SokobanOn a board of at most 12 by 12 with up to 5 boxes that must stay edge-connected, find the fewest box pushes to reach the goal arrangement.	Medium6	BFSSimulation+1	No attempts yet	5s	512 MB	Judgeable
Alphabetomials (Small)Given a degree-4 polynomial and a dictionary, sum its value over all phrases of up to K dictionary words, modulo 10009.	Medium6	Dynamic programmingMath+2	No attempts yet	5s	512 MB	Judgeable
Football Team PhotoEach player must differ in color from the next player to the right within one row of their row; find the minimum number of colors.	Medium6	GraphSorting+1	No attempts yet	5s	512 MB	Judgeable
Football Team (Large)Find the minimum number of colors needed so that each player differs from the nearest right neighbor in the same or adjacent row.	Medium6	GraphGreedy+1	No attempts yet	5s	512 MB	Judgeable
All Your Base (Small)Each test string is a numeral in an unknown base, with distinct symbols for distinct digits; find the smallest value it can represent, avoiding leading zeros.	Medium6	GreedyMath+2	No attempts yet	5s	512 MB	Judgeable
Center of Mass of a Firefly SwarmEach firefly moves linearly at constant velocity; find the minimum distance from the origin to the swarm's center of mass over t >= 0 and the earliest time it occurs, printed to eight exact decimals.	Medium6	MathGeometry+2	No attempts yet	5s	512 MB	Judgeable
The Next Number (Large)Given N, find the next integer whose count of each nonzero digit matches that of N, with zeros unrestricted.	Medium6	CombinatoricsGreedy+2	No attempts yet	5s	512 MB	Judgeable
Multi-base happy numbersFor each set of bases, find the smallest integer above 1 whose repeated digit-square iteration reaches 1 in every listed base.	Medium6	MathSimulation+1	No attempts yet	5s	512 MB	Judgeable
Ping Pong Balls (Large)Given two fixed displacement vectors and a grid, count how many traps a single strike triggers by a branching cascade, where the grid can hold 10^12 cells.	Medium6	GraphImplementation+1	No attempts yet	5s	512 MB	Judgeable
Mine Layer (Small)Given a small Minesweeper-style clue grid (R is 3 or 5, C is 3 to 5), find the maximum number of mines the middle row can hold over all layouts that match the clues.	Medium6	Brute forceBacktracking+2	No attempts yet	5s	512 MB	Judgeable
Triangle TransformationGiven two triangles where the second lies inside the first, find the fixed point of the rotation, scaling, and translation map taking one to the other.	Medium6	GeometryMath+1	No attempts yet	5s	512 MB	Judgeable
Rainbow TreesCount edge colorings of a small tree with k colors so that any two or three consecutive edges on a path get distinct colors, modulo 1e9+9.	Medium6	Dynamic programmingTree+1	No attempts yet	5s	512 MB	Judgeable
Mixing Bowls (Small)Given a recipe tree of mixtures, find the minimum number of bowls needed by choosing the order of preparation.	Medium6	TreeDFS+1	No attempts yet	5s	512 MB	Judgeable
King (Small)On a board of at most 16 squares with burned cells, a king moves to unvisited neighbors; decide who wins under optimal play.	Medium6	Game theoryDFS+1	No attempts yet	5s	512 MB	Judgeable
Modern Art PlagiarismDecide whether the smaller tree is isomorphic to some subtree cut from the larger tree.	Medium6	TreeDFS+1	No attempts yet	50s	512 MB	Judgeable
IgraGiven two length-N strings over {a,b,c}, permute the multiset from the second so no position matches the first and the result is lexicographically smallest.	Medium6	GreedyString+1	No attempts yet	1s	64 MB	Judgeable
Endless Knight (Small)Count monotone right-and-down knight paths from (1,1) to (H,W) on a grid, avoiding up to 10 blocked squares, modulo 10007.	Medium6	Dynamic programmingCombinatorics	No attempts yet	5s	512 MB	Judgeable
Triangle AreasGiven N, M, A, find three lattice points in an N by M grid forming a triangle of area exactly A/2, printing the lexicographically smallest coordinate sequence or IMPOSSIBLE.	Medium6	GeometryMath+2	No attempts yet	5s	512 MB	Judgeable
PermRLE (Small)Split the string into fixed blocks of length k, permute each block the same way, and minimize the number of runs in the result over all k! permutations.	Medium6	Brute forceSorting+2	No attempts yet	5s	512 MB	Judgeable
Ugly Numbers (Large)Count expressions formed by inserting plus, minus, or nothing between digits whose evaluated value is divisible by 2, 3, 5, or 7.	Medium6	Dynamic programmingNumber theory+1	No attempts yet	5s	512 MB	Judgeable
Increasing Speed LimitsGiven a sequence generated by a small recurrence, count strictly increasing subsequences by position, modulo 1000000007.	Medium6	Dynamic programmingSorting+2	No attempts yet	5s	512 MB	Judgeable
Crop Triangles (Large)Generate n points with a given recurrence and count triples whose coordinate sums are divisible by 3 on both axes.	Medium6	MathCombinatorics+1	No attempts yet	5s	512 MB	Judgeable
Number SetsGiven an interval [A, B] and a prime threshold P, merge any two numbers sharing a prime factor >= P, then count the remaining sets.	Medium6	Union-findNumber theory+1	No attempts yet	5s	512 MB	Judgeable
Number Sets (Large)Given an interval of consecutive integers and a threshold P, merge pairs sharing a prime factor of at least P, then count the remaining sets.	Medium6	Union-findNumber theory+2	No attempts yet	50s	512 MB	Judgeable
Last three digits of (3 + √5)^nCompute the last three digits before the decimal point of (3 + sqrt(5))^n for n up to two billion.	Medium6	MathNumber theory+1	No attempts yet	5s	512 MB	Judgeable
Pat PatAfter point swaps in an array, answer queries asking whether a subarray is nondecreasing.	Medium6	Segment treeArray	No attempts yet	1s	256 MB	Judgeable
Mixture (Small)Find the amounts of two mixtures a and b maximizing revenue under shared material limits, then round the optimum to two decimals.	Medium6	GeometryBrute force+2	No attempts yet	1s	256 MB	Judgeable
Stacking PancakesGiven a stack of up to 6 pancakes with distinct sizes and sides, find the minimum number of prefix flips to sort sizes descending and turn all fronts up.	Medium6	BFSBrute force+1	No attempts yet	2s	256 MB	Judgeable
SwapGiven a permutation, decide for each k = 2..n whether to swap position k with floor(k/2), producing the lexicographically smallest reachable sequence.	Medium6	GreedyTree+1	No attempts yet	1s	256 MB	Judgeable
Stone BridgeGiven two stick powers A and B, find the fewest moves from stone N to stone M using +-1, +-A, +-B, and multiply-by-A/B moves on a bridge of stones 0 to 100000.	Medium6	BFSGraph+1	No attempts yet	1s	128 MB	Judgeable
Don't be lateGiven an undirected weighted graph with per-edge time and fare, find the minimum total fare of a path from node 1 to node N whose total time is at most T.	Medium6	Shortest pathGraph+2	No attempts yet	2s	128 MB	Judgeable
Junha at the Internet LoungeGiven N people each using a lounge over a fixed interval and always taking the lowest-numbered free seat, find the minimum number of seats so nobody waits, and the usage count of each seat.	Medium6	SortingHeap+2	No attempts yet	1s	128 MB	Judgeable
Multiplication GameGiven a set of allowed digits, find the fewest factors (minus one) whose digits all come from the set and whose product is K.	Medium6	Dynamic programmingNumber theory	No attempts yet	1s	128 MB	Judgeable
Republic of InhanicaGiven a tree rooted at island 1, cut a minimum-cost set of edges so that every leaf other than the root is disconnected from the root.	Medium6	TreeDynamic programming	No attempts yet	1s	256 MB	Judgeable
Rigging the DrawGiven a functional graph on N positions, find the smallest k between 2 and 2e9 such that applying the map k times sends every position away from itself.	Medium6	GraphSimulation+2	No attempts yet	1s	256 MB	Judgeable
Gennady is smartMaintain counts on a hexagonal grid; each update adds 1 to all cells within distance r of (x, y), and queries ask for a single cell's value.	Medium6	Prefix sumMatrix+1	No attempts yet	2s	256 MB	Judgeable
PalinilapA lowercase string may be modified at exactly one position or left alone; find the maximum number of palindromic substrings achievable.	Medium6	StringDynamic programming+1	No attempts yet	1s	512 MB	Judgeable
Binary string restorationGiven counts of each of the four adjacent pairs, build the lexicographically smallest binary string of length a+b+c+d+1 that realizes them, or report impossible.	Medium6	StringGreedy+2	No attempts yet	2s	256 MB	Judgeable
New TreeGiven point A and a new tree, find the smallest pair (B, C) so triangle ABC is counterclockwise, contains the new tree strictly, and contains no other old tree.	Medium6	GeometryBrute force	No attempts yet	0.2s	1024 MB	Judgeable
UniversitiesOn a tree whose nodes are black or white with weighted happiness, find the maximum total weight of a path that contains equally many black and white nodes.	Medium6	TreePrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Lexicographic SortingCount subsets of the integers in [A, B] whose lexicographic order as strings matches their numerical order, modulo 1e9+7.	Medium6	SortingString+1	No attempts yet	1s	1024 MB	Judgeable
Three-Way JunctionSimulate ants moving on a three-road junction where collisions reverse them and solo arrivals at the center turn right; report total travel time and arrivals per endpoint.	Medium6	SimulationImplementation+1	No attempts yet	1s	512 MB	Judgeable
London UndergroundGiven subway lines with stop times and a line-change cost, find the minimum travel time between two stations.	Medium6	Shortest pathGraph+1	No attempts yet	1s	512 MB	Judgeable
Fried Soboro BunsGiven how many buns were eaten, find which person picked up the last bun when person i grabs a bun at multiples of t_i, ties broken by smaller index.	Medium6	Binary searchSorting+1	No attempts yet	1s	512 MB	Judgeable
Double MajorGiven courses split into two departments and overlap pairs between them, find the largest set of courses with no overlapping pair.	Medium6	GraphUnion-find+2	No attempts yet	5s	512 MB	Judgeable
Card Fusion EventMerge adjacent cards until one remains, where a merge pays the sum of both levels and keeps only the left card's level; maximize total gold.	Medium6	IntervalsDynamic programming	No attempts yet	1s	512 MB	Judgeable
A Scary Part-Time JobGiven daily wages, choose a contiguous range maximizing (length of range) times (minimum wage in that range).	Medium6	StackGreedy	No attempts yet	1s	512 MB	Judgeable
Stick GamePlace non-overlapping horizontal sticks of given lengths on a grid with obstacles; find the winner under optimal play.	Medium6	Game theoryImplementation	No attempts yet	1s	512 MB	Judgeable
Jumping MinhoBuy a cheapest subset of jump lengths so every integer on the line is reachable from the start; print -1 if impossible.	Medium6	Dynamic programmingNumber theory+1	No attempts yet	2s	512 MB	Judgeable
Placing Two SnakesCount ordered placements of two non-overlapping 1-wide rectangles (Kiki length k, Susu length s) on an n by m grid, modulo 1e9+7, with direction distinguishing head from tail.	Medium6	MathCombinatorics+1	No attempts yet	2s	512 MB	Judgeable
MutaliskGiven the health of at most 3 SCVs, find the fewest attacks that deal 9, 3, 1 damage in some order to distinct SCVs and destroy them all.	Medium6	Dynamic programmingBrute force	No attempts yet	2s	512 MB	Judgeable
PlaylistCount length-P sequences over N songs where every song appears at least once and any two copies of the same song are separated by at least M other songs.	Medium6	Dynamic programmingCombinatorics+2	No attempts yet	2s	512 MB	Judgeable
Royal DecreeGiven a friendship graph and bound d, find the largest possible difference between richest and poorest that satisfies the friend-difference constraint, or -1 if unbounded.	Medium6	GraphShortest path+1	No attempts yet	2s	512 MB	Judgeable
Painting blocksCount colorings of N blocks with 4 colors so that the number of red and yellow blocks are both even, modulo 10007.	Medium6	CombinatoricsMath+2	No attempts yet	2s	512 MB	Judgeable
Minimum weight spread for strong connectivityPick a strongly connected subgraph of a complete directed graph so the chosen edges' weight range is as small as possible.	Medium6	GraphSorting+2	No attempts yet	2s	512 MB	Judgeable
Stone GroupsStarting from stone counts A, B, C, repeatedly double the smaller of two unequal groups and subtract it from the larger; decide whether all three can become equal.	Medium6	BFSMath+2	No attempts yet	2s	512 MB	Judgeable
Path GameGiven a 2 by M grid of white and black cells with a guaranteed left-right white path, find the maximum number of white cells that can be turned black while keeping some left-right path.	Medium6	Dynamic programmingGraph+2	No attempts yet	2s	512 MB	Judgeable
Equivalent StringsDecide whether two equal-length strings are equivalent under recursive splitting and optional swap of halves.	Medium6	Divide and conquerString+2	No attempts yet	2s	512 MB	Judgeable
Colorful VillageMaintain N houses under range repaint operations and answer queries counting how many of the T colors appear in a range.	Medium6	Segment treeBit manipulation+2	No attempts yet	2s	512 MB	Judgeable