Problems
Pick a problem and write your solution in the built-in editor. The judge runs it against real test cases while you watch, and the wider archive is open to read whenever you like.
Total results3,702 problems
| Title | Level | Topics | Solved | Time limit | Memory limit | Judge |
|---|---|---|---|---|---|---|
| Parenthesis String ?Answer M queries asking whether substring S[i..j] is a correct bracket sequence, and output the sum of all answers. | Medium6 | Prefix sumStack+1 | No attempts yet | 0.5s | 512 MB | Judgeable |
| Bracket StringsGiven N and K, find the K-th lexicographically smallest string of length N over '(' and ')' that is not a valid bracket string, using combinatorial counting. | Medium7 | CombinatoricsDynamic programming+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Smallest Integer with K Distinct DigitsGiven N up to 10^18 and K up to 10, construct the smallest integer at least N that contains exactly K distinct decimal digits. | Medium7 | Dynamic programmingGreedy+2 | No attempts yet | 2s | 128 MB | Judgeable |
| DNA Deletions and Protein CountCount, modulo 1e9+7, the distinct proteins obtainable by deleting some nucleotides from a DNA string and translating the remaining codons via a given table. | Medium7 | Dynamic programmingGreedy+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Palindrome FactoryCompute the minimum number of insertions, deletions, replacements, and at most one swap needed to turn a given string into a palindrome. | Medium7 | Dynamic programmingString+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Twin VillagesSelect as many village pairs as possible with Manhattan distance at least D and degree at most P per village, then minimize the total distance among maximum selections. | Medium7 | Dynamic programmingBit manipulation+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Coin Board GameA coin on a grid jumps exactly the digit on its cell in one of four directions; find the maximum number of moves before it leaves the board or hits a hole, or -1 if it can move forever. | Medium7 | Dynamic programmingDFS+2 | No attempts yet | 2s | 512 MB | Judgeable |
| Counting K-gonsCount the subsets of exactly K segments (from N, N up to 50) whose longest side is shorter than the sum of the rest, forming a valid K-gon. | Medium7 | Dynamic programmingCombinatorics+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Restore an Addition EquationFill the ? digits in an addition equation A+B=C with digits (no leading zeros) so the sum holds, maximizing C then A. | Medium7 | Dynamic programmingGreedy+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Placing Puzzle PiecesGiven a board length and a set of piece lengths, find the minimum number of pieces to place so that no remaining piece can fit in any leftover gap. | Medium7 | Dynamic programmingGreedy+2 | No attempts yet | 2s | 128 MB | Judgeable |
| BackupGiven n sorted company positions on a line, choose k disjoint pairs (2k companies) minimizing the total sum of pairwise distances. | Medium7 | GreedyHeap+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Oh Min-sik's WorryFind the maximum money achievable traveling from city A to city B using weighted directed edges and city rewards, detecting infinite gain via positive cycles. | Medium7 | GraphShortest path+2 | No attempts yet | 2s | 128 MB | Judgeable |
| ParliamentGiven seat counts for N parties, find the maximum-seat coalition that has more than half the total seats but loses majority if any single member is removed. | Medium7 | Dynamic programmingSorting+1 | No attempts yet | 2s | 128 MB | Judgeable |
| WarGiven a forest of vassal relations and per-country conquest costs, find the minimum days needed to conquer or force surrender of at least M countries using tree knapsack DP. | Medium7 | Dynamic programmingTree+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Stock King DonghoGiven prices for C stocks over D days and starting cash M, find the maximum cash obtainable by buying and selling whole shares each day using knapsack-style dynamic programming. | Medium7 | Dynamic programmingArray+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Palindrome Word SequencesCount ordered sequences of given words, reused any number of times, whose concatenation has exact length L and forms a palindrome. | Medium7 | Dynamic programmingString matching+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Special NodesIn a rooted tree where child weights exceed parent weights, mark vertices special or ordinary to minimize the total of each ordinary vertex's weight minus its nearest special ancestor's weight. | Medium7 | Dynamic programmingTree+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Custom DiceCount six-faced dice with distinct positive integers averaging at most M, treating rotations as identical, and print the count mod 1e9+7. | Medium7 | CombinatoricsDynamic programming+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Gem Shop LightingGiven required light values for an N by M grid of gems, find the minimum total intensity of row and column lamps so every gem's light requirement is met, which reduces to a maximum weight bipartite matching problem. | Medium7 | GraphDynamic programming+1 | No attempts yet | 5s | 128 MB | Judgeable |
| BiomagnificationGiven a DAG of predator-prey species where each consumer picks prey via an unbounded knapsack to meet its calorie need while minimizing heavy metal, determine if the human species survives and find its minimum accumulated metal. | Medium7 | Dynamic programmingGraph+2 | No attempts yet | 5s | 128 MB | Judgeable |
| Bead NecklaceCount distinct linear arrangements of beads with given color counts (3 to 5 colors, up to 35 beads total) so that every three consecutive beads have different colors. | Medium7 | CombinatoricsMath+2 | No attempts yet | 2s | 128 MB | Judgeable |
| RPGGiven quests that require either a strength or intelligence threshold and grant points to freely raise those stats, find the maximum number of quests completable. | Medium7 | Dynamic programmingSorting+2 | No attempts yet | 2s | 128 MB | Judgeable |
| High-Rise BuildingsCount permutations of heights 1..N arranged so exactly L buildings are visible from the left and R from the right, modulo 1e9+7. | Medium7 | CombinatoricsDynamic programming+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Number of NKD SequencesCount length-K strictly increasing sequences summing to N where consecutive differences are at most D and the first term is at most D, modulo 1e9+7. | Medium7 | Dynamic programmingCombinatorics+2 | No attempts yet | 2s | 512 MB | Judgeable |
| Candy Stair ClimbFind the maximum candies collectible by jumping between horizontal stair segments within distance K, never decreasing height, starting from the ground. | Medium7 | Topological sortGraph+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Ideal StringBuild the lexicographically smallest length-N string where each character's total occurrence count equals the position of its first appearance, or output -1 if none exists. | Medium7 | GreedyDynamic programming+2 | No attempts yet | 2s | 128 MB | Judgeable |
| TetrisCount the number of ways to tile a 3xN grid using square, T, S, Z, L, and J tetrominoes (no straight piece), modulo 1,000,000. | Medium7 | Dynamic programmingCombinatorics+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Coin ProblemFind the minimum number of coins from denominations 10^K and 25x100^K needed to make an exact price up to 10^15. | Medium7 | GreedyMath+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Fan ServiceCount length-2K ticket numbers over a given digit set where the two halves have equal digit sums or the odd/even positions have equal digit sums, modulo 999983. | Medium7 | Dynamic programmingCombinatorics+1 | No attempts yet | 2s | 128 MB | Judgeable |
| MarriageGiven up to 12 men and 12 women with mutual liking pairs, partition everyone into star-shaped marriages (one person of one gender with several of the other) to cover all people with the fewest marriages, or report impossibility. | Medium7 | Dynamic programmingBit manipulation+2 | No attempts yet | 5s | 128 MB | Judgeable |
| Paper OverlayOverlay two grid papers, each freely rotated, flipped, and positioned, then find the largest all-X rectangle in the combined grid. | Medium7 | MatrixBrute force+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Fixing an ArrayFor each array value, find the number within a given range that has the smallest Hamming distance in binary, breaking ties by choosing the smallest value. | Medium7 | Bit manipulationDynamic programming+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Olympic RankingGiven current medal counts, decide how to award all remaining silver and bronze medals so that team 1 (which wins every remaining gold) reaches the best possible final rank. | Medium7 | Dynamic programmingGreedy+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Dial LockGiven a current dial state and a password of N digits, find the minimum number of operations, each rotating a contiguous block of at most three circular dials by 1 to 3 steps, to reach the password. | Medium7 | Dynamic programmingMath+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Number of Routes Arriving at the Exact TimeCount the number of routes from S to E in a weighted directed graph that take exactly T minutes, modulo 1,000,003. | Medium7 | MatrixGraph+2 | No attempts yet | 2s | 128 MB | Judgeable |
| New OperatorGiven digit-based functions and a custom operator @ built from them, find the minimum number of @ operations starting from X to reach target value G, or report -1. | Medium7 | MathDynamic programming+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Stair NumbersCount N-digit numbers whose adjacent digits differ by exactly 1 and that contain every digit 0-9 at least once, modulo 1,000,000,000. | Medium7 | Dynamic programmingBit manipulation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Treasure HuntGiven a grid where the player travels down-right, then up-left, then down-right again, find the maximum treasure collected counting each cell only once per visit. | Medium7 | Dynamic programmingMatrix+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Traffic EnforcementGiven shuffled entry and exit times for N cars, pair them into valid entry-exit matches and find the minimum and maximum total speeding fine over all valid perfect matchings. | Medium7 | GraphDynamic programming+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Youngsik FunctionCount integers in [A, B] up to 1e9 whose repeated adjacent-digit-difference reduction (the Youngsik function) eventually collapses to the single digit 7. | Medium7 | Dynamic programmingRecursion+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Once Opened, You Can't StopChoose one integer per flavor within its given range so the sum of absolute changes between consecutive picks is minimized, and output the values. | Medium7 | Dynamic programmingGreedy+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Counting Single-Letter TrianglesCount all size-2-or-larger right isosceles and diamond-shaped isosceles triangles made of one repeated letter, in any rotation, inside an N x N grid. | Medium7 | Dynamic programmingMatrix+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Maximum Increasing Rectangle SetGiven N rectangles, find the maximum subset that can be strictly ordered by lower-left to upper-right containment, solvable via DP with a segment tree over compressed coordinates. | Medium7 | Dynamic programmingSegment tree+2 | No attempts yet | 2s | 128 MB | Judgeable |
| MusicInsert non-consecutive rest symbols into three note sequences to equalize their lengths while maximizing a column-matching score, or report impossibility. | Medium7 | Dynamic programmingString+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Top Shelf of the BookshelfPick up to 10 book titles, sorted lexicographically, so that no two neighboring titles share the same letter at any aligned alphabetic position, maximizing total preference score. | Medium7 | Dynamic programmingString+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Number Game 2Given a set of integers and a cap K on how many may be summed, find the first integer that cannot be formed and decide which player loses at that turn. | Medium7 | Dynamic programmingMath+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Trash CleanupGiven a grid with trash cells, find the minimum number of top-left-to-bottom-right monotone paths needed to cover every trash cell. | Medium7 | Dynamic programmingSorting+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Racing ResultsCount how many full car rankings are consistent with given pairwise 'beat' results, essentially counting linear extensions of a partial order mod 1,000,003. | Medium7 | Dynamic programmingCombinatorics+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Inverse Descent PermutationsCount permutations of size N with a fixed first element F whose inverse permutation has exactly K descents. | Medium7 | CombinatoricsDynamic programming+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Farmland LevelingGiven N heights forming a 1D terrain, find the minimum number of unit cells to remove so that the number of resulting peaks is at most K. | Medium7 | Dynamic programmingGreedy+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Number PairingGiven an N x 3 grid, find a perfect domino tiling that maximizes and minimizes the total sum of absolute differences over all pairs. | Medium7 | Dynamic programmingGreedy+1 | No attempts yet | 2s | 128 MB | Judgeable |
| BallerinoFind the minimum extra cushions needed for a knight-move dancer to reach the goal on a grid with stones, and count how many minimal cushion sets work. | Medium7 | Shortest pathBFS+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Parcel DeliveryGiven each parcel's destination branch along a line, find the minimum cost to deliver all parcels using per-distance trucks and fixed-cost multi-parcel helicopter trips. | Medium7 | Dynamic programmingSorting+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Tetris StackingGiven a sequence of up to 100 Tetris pieces falling into a width-3 field, choose each piece's rotation and column to minimize the final stack height. | Medium7 | Dynamic programmingSimulation+2 | No attempts yet | 2s | 128 MB | Judgeable |
| Seat SwappingGiven N students each with a team label (K up to 8), find the minimum adjacent swaps to group each team into one contiguous block in some chosen team order. | Medium7 | Dynamic programmingBit manipulation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Expression RepresentationCompute the minimum number of 1-symbols needed to build an integer n using +, *, ! and parentheses, using DP over factorial and multiplicative decompositions. | Medium7 | Dynamic programmingMath+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Bookcase ConstructionPartition n books into three non-empty groups to minimize the sum of per-shelf maximum heights times the maximum total thickness of any shelf. | Medium7 | Dynamic programmingSorting+1 | No attempts yet | 5s | 128 MB | Judgeable |
| Ladder GameGiven a ladder diagram, find the minimum cost of removing existing rungs and adding new rungs so a traveler starting at column a ends at column b. | Medium7 | Dynamic programmingSimulation+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Increasing SequenceGiven a digit string up to 80 characters, split it into a strictly increasing sequence of integers (leading zeros allowed) minimizing the last number's value. | Medium7 | Dynamic programmingString+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Number GameGiven a sequence of numbers, determine the winner of a two-player suffix-removal game where each player takes a suffix block ending at the current rightmost element and minimizes their own total sum, for three separate games with n up to 3000. | Medium7 | Dynamic programmingGame theory+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Wire ConnectionDecide whether a subset of given semicircular wires can be joined end to end, with free rotation at joints, to form one closed non-overlapping loop. | Medium7 | GeometryDynamic programming+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Counting Base RepresentationsCount the ways to split a digit string into a base suffix and a sequence of no-leading-zero digit values all less than that base. | Medium7 | Dynamic programmingString+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Image EnergyAssign each grid cell to black or white to minimize per-cell cost plus adjacency mismatch cost, solvable via min-cut on a grid graph. | Medium7 | GraphDynamic programming+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Final Drive RouteGiven a graph where only minimum-fatigue outgoing edges per city are usable, find the S to T route minimizing total fatigue then total length, detecting unreachable or unbounded (negative cycle) cases. | Medium7 | GraphShortest path+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Chip ConstructionGiven N component priorities and K non-crossing power lines each serving up to two components, find a nesting-valid pairing that maximizes total sum of squares/products. | Medium7 | Dynamic programmingGreedy+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Building a TournamentGiven a sequence of distinct ranks, build a bracket by repeatedly merging adjacent intervals (like matches in a tournament) minimizing the total sum of absolute rank differences over all merges. | Medium7 | Dynamic programmingDivide and conquer+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Drawing a Mountain RangeGiven n polyline points, choose K interior points (plus both endpoints) to form an approximating polyline that minimizes the total area between it and the original mountain outline. | Medium7 | Dynamic programmingGeometry+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Turning Off StreetlightsFind the optimal order to switch off all streetlights on a line, starting from a given position, minimizing sum of power times shutoff time, a classic interval DP problem. | Medium7 | Dynamic programmingGreedy+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Binary Tree DrawingGiven a binary tree reconstructed from preorder and inorder traversals, compute the minimum area of a grid drawing where each right child extends the row and each down child extends the column. | Medium7 | Dynamic programmingTree+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Three-Way CallFind a minimum-cost subtree (Steiner tree) connecting three given switches in a weighted graph and output the cost and chosen edges. | Medium7 | GraphShortest path+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Maximum String PastingGiven a long string and up to 500 short patterns, find all their occurrences and select non-overlapping intervals to maximize total covered length via DP. | Medium7 | String matchingDynamic programming+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Department AssignmentGiven friend/rival constraints among N employees, decide via union-find with parity whether a bipartition exists and, if so, find the split minimizing the size difference between two groups using a subset-sum style DP over component sizes. | Medium7 | Union-findDynamic programming+1 | No attempts yet | 1s | 128 MB | Judgeable |
| BookshelfPartition an ordered sequence of books into contiguous shelves to minimize the max of total shelf-height sum and the largest shelf-width, using binary search plus greedy/DP feasibility check. | Medium7 | Binary searchGreedy+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Mobile Binary NumberGiven a nested-bar mobile whose bars may each be flipped independently, find the K-th lexicographically smallest distinct binary string obtainable across all flip combinations. | Medium7 | Dynamic programmingRecursion+2 | No attempts yet | 1s | 128 MB | Judgeable |
| Crossing SegmentsGiven segments between two parallel lines that are 2-colorable by non-crossing constraint, find the longest chain where consecutive segments cross. | Medium7 | Dynamic programmingSorting+1 | No attempts yet | 1s | 128 MB | Judgeable |
| High-Speed RailwayCount subsets of interval-graph vertices forming a vertex cover of the interval overlap graph, modulo a given number. | Medium7 | IntervalsDynamic programming+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Car RaceGiven a directed graph with no cycles avoiding vertex 1, find the maximum-score simple route from checkpoint 1 back to checkpoint 1 and print it. | Medium7 | GraphDynamic programming+1 | No attempts yet | 1s | 128 MB | Judgeable |
| DNA SimilarityFind the lexicographically smallest longest common subsequence of two DNA strings where adjacent picked characters in each string must be within index-distance K. | Medium7 | Dynamic programmingString | No attempts yet | 1s | 128 MB | Judgeable |
| Connecting RectanglesGiven N candidate axis-aligned rectangles with weights equal to their index, select a maximum-weight subset of pairwise non-overlapping and non-touching rectangles. | Medium7 | Dynamic programmingGreedy+2 | No attempts yet | 1s | 128 MB | Judgeable |
| Optimizing Mobile Phone Text EntryPartition the 26 letters into K ordered contiguous groups (max 8 each) to minimize frequency-weighted key presses, breaking ties by lexicographically smallest concatenated output. | Medium7 | Dynamic programmingGreedy+2 | No attempts yet | 1s | 128 MB | Judgeable |
| Secret WordsGiven secret words and a target string, find minimum total rearrangement cost to build the target by concatenating (possibly rearranged) copies of the words, or -1 if impossible. | Medium7 | Dynamic programmingString+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Romantic KingGiven a grid with a start, an end, and up to 16 gift trees where movement speed decreases with carried gifts, find the maximum number of gifts deliverable within a time limit. | Medium7 | BFSDynamic programming+1 | No attempts yet | 10s | 128 MB | Judgeable |
| Business ExpansionGiven a directed graph, find a walk from city 1 to city 2 and back to city 1 that minimizes the number of distinct visited cities. | Medium7 | Shortest pathGraph+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Function Return ValueGiven N nested loops whose bounds are either fixed integers or an outer loop variable, compute the total iteration count modulo 1e9+7. | Medium7 | Dynamic programmingCombinatorics+2 | No attempts yet | 1s | 128 MB | Judgeable |
| GremlinsGiven a graph of gremlin reproduction with hatching and growth delays over T years (T up to 10^15), compute the maximum number of ancestors any gremlin has. | Medium7 | Dynamic programmingGraph+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Clearing the BeadsFind the minimum number of beads to insert between colored beads so every bead can eventually be cleared by removing runs of length at least K. | Medium7 | Dynamic programmingStack+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Explosion-Safe FoldingCount ways to fold N tape pieces at seams (straight or 180 degree) so coated faces never touch, given coating patterns from both ends, modulo 10301. | Medium7 | Dynamic programmingCombinatorics+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Strange PainterReconstruct a picture painted by a recursive quadrant-coloring process closest (in Hamming distance) to a given N x N binary target, then output that minimal difference and the picture. | Medium7 | Divide and conquerDynamic programming+1 | No attempts yet | 1s | 128 MB | Judgeable |
| A=SInsert plus signs between digits of a huge number A so the resulting sum equals a small target S, using as few plus signs as possible. | Medium7 | Dynamic programmingString+1 | No attempts yet | 1s | 128 MB | Judgeable |
| VictoryCount first moves in a circular pick-up game with adjacency constraints that force a win for the first player against an optimal second player counting odd numbers picked. | Medium7 | Dynamic programmingGame theory+1 | No attempts yet | 1s | 128 MB | Judgeable |
| HousewarmingGiven a grid with blocked cells, find the maximum rectangle of empty cells and output twice its width plus height (the perimeter). | Medium7 | Dynamic programmingStack+1 | No attempts yet | 1s | 128 MB | Judgeable |
| CookiesCount, modulo 10007, the number of orders of choosing cookies on a circle so that each chosen cookie's two current neighbors always match in flavor, until 1 or 2 remain. | Medium7 | Dynamic programmingCombinatorics+1 | No attempts yet | 5s | 128 MB | Judgeable |
| BakeryGiven a grid where pipelines move from the first column to the last column stepping right, diagonal-up-right or diagonal-down-right without sharing cells, find the maximum number of vertex-disjoint such paths. | Medium7 | GraphGreedy+1 | No attempts yet | 1s | 256 MB | Judgeable |
| LakeCount simple cycles in a fixed circular ladder graph with some edges removed, given three binary strings of usable inner, outer, and bridge edges, modulo 1e9+7. | Medium7 | GraphDynamic programming+1 | No attempts yet | 1s | 128 MB | Judgeable |
| BulbsGiven a target 2×N binary grid, find the minimum number of toggle operations on contiguous row or column segments to reach that pattern. | Medium7 | Dynamic programmingGreedy+1 | No attempts yet | 1s | 128 MB | Judgeable |
| HighwayGiven a road profile and costs for flat, sloped, tunnel or viaduct travel, find the minimum time to cross using at most K equal-height shortcut structures. | Medium7 | Dynamic programmingGreedy+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Railway Route CoverGiven a tree, partition all vertices into vertex-disjoint paths covering every node so that the total edge weight used by the paths is maximized, using tree DP. | Medium7 | Dynamic programmingTree+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Pilot CrewsGiven pilots sorted by age with captain and assistant salaries, pair them into captain-older-than-assistant crews minimizing total salary paid. | Medium7 | GreedySorting+1 | No attempts yet | 1s | 128 MB | Judgeable |
| Jozo's Train TripGiven stations, railways, and scheduled trains, find the minimum station-waiting time for a trip starting at station 1 at time 1 and returning to station 1 within a given time window. | Medium7 | Shortest pathGraph+1 | No attempts yet | 2s | 128 MB | Judgeable |
| Two Snow PlowsGiven a tree rooted at S, find minimum total edge traversal cost for two walks starting at S that together cover every edge, without returning to S. | Medium7 | TreeDynamic programming+1 | No attempts yet | 1s | 128 MB | Judgeable |