General
Introductory Problems
- Weird Algorithm99539 / 104269
- Missing Number84722 / 89375
- Repetitions73994 / 77518
- Increasing Array69084 / 71994
- Permutations60756 / 62836
- Number Spiral43001 / 46907
- Two Knights32263 / 33425
- Two Sets34861 / 37893
- Bit Strings40597 / 42881
- Trailing Zeros38002 / 40648
- Coin Piles33475 / 36948
- Palindrome Reorder30579 / 32607
- Gray Code19033 / 21774
- Tower of Hanoi17744 / 18509
- Creating Strings26370 / 27175
- Apple Division25589 / 29367
- Chessboard and Queens15203 / 15521
- Digit Queries10283 / 12370
- Grid Paths6326 / 8094
Sorting and Searching
- Distinct Numbers46710 / 51209
- Apartments34061 / 38715
- Ferris Wheel32410 / 35457
- Concert Tickets25926 / 30890
- Restaurant Customers26641 / 29091
- Movie Festival25057 / 26795
- Sum of Two Values29563 / 33736
- Maximum Subarray Sum29131 / 30646
- Stick Lengths25797 / 27254
- Missing Coin Sum18036 / 18776
- Collecting Numbers18685 / 20239
- Collecting Numbers II7436 / 9746
- Playlist19373 / 22612
- Towers19869 / 21505
- Traffic Lights15559 / 17541
- Josephus Problem I10603 / 12026
- Josephus Problem II6136 / 8008
- Nested Ranges Check6028 / 7092
- Nested Ranges Count4290 / 4960
- Room Allocation11334 / 13200
- Factory Machines14680 / 16454
- Tasks and Deadlines13184 / 13499
- Reading Books10505 / 11295
- Sum of Three Values15319 / 17384
- Sum of Four Values9715 / 10993
- Nearest Smaller Values12955 / 13471
- Subarray Sums I16744 / 18034
- Subarray Sums II15486 / 17683
- Subarray Divisibility13580 / 14988
- Subarray Distinct Values7742 / 8391
- Array Division12429 / 13202
- Sliding Window Median8225 / 9409
- Sliding Window Cost5724 / 6591
- Movie Festival II7080 / 8585
- Maximum Subarray Sum II6483 / 7785
Dynamic Programming
- Dice Combinations46074 / 49103
- Minimizing Coins39665 / 42959
- Coin Combinations I36457 / 39801
- Coin Combinations II30609 / 35149
- Removing Digits33842 / 34719
- Grid Paths32155 / 33248
- Book Shop28300 / 31669
- Array Description20426 / 23059
- Counting Towers11649 / 12368
- Edit Distance21198 / 22549
- Rectangle Cutting17689 / 19416
- Money Sums21121 / 22068
- Removal Game15072 / 16771
- Two Sets II16644 / 18188
- Increasing Subsequence17117 / 19457
- Projects11508 / 13072
- Elevator Rides6963 / 8962
- Counting Tilings3974 / 4376
- Counting Numbers5355 / 6114
Graph Algorithms
- Counting Rooms31455 / 33485
- Labyrinth20634 / 25659
- Building Roads27217 / 28387
- Message Route23136 / 24267
- Building Teams22212 / 23348
- Round Trip17231 / 19045
- Monsters10872 / 13396
- Shortest Routes I18487 / 21130
- Shortest Routes II15621 / 17143
- High Score7841 / 12875
- Flight Discount10912 / 13383
- Cycle Finding8102 / 10210
- Flight Routes7529 / 8496
- Round Trip II9050 / 10402
- Course Schedule12539 / 13109
- Longest Flight Route7753 / 10426
- Game Routes9065 / 9995
- Investigation6655 / 7240
- Planets Queries I5622 / 6871
- Planets Queries II2253 / 2800
- Planets Cycles3758 / 4237
- Road Reparation8995 / 9461
- Road Construction9487 / 9862
- Flight Routes Check8074 / 8926
- Planets and Kingdoms6506 / 6793
- Giant Pizza2638 / 2973
- Coin Collector4062 / 4606
- Mail Delivery3514 / 3913
- De Bruijn Sequence1887 / 1988
- Teleporters Path2782 / 3118
- Hamiltonian Flights3899 / 4443
- Knight's Tour1645 / 1951
- Download Speed2729 / 3860
- Police Chase2208 / 2537
- School Dance2431 / 2593
- Distinct Routes1583 / 2152
Range Queries
- Static Range Sum Queries21437 / 22442
- Static Range Minimum Queries15942 / 17071
- Dynamic Range Sum Queries16427 / 17202
- Dynamic Range Minimum Queries14950 / 15358
- Range Xor Queries15098 / 15332
- Range Update Queries12034 / 12985
- Forest Queries11798 / 12289
- Hotel Queries8622 / 9119
- List Removals7187 / 7597
- Salary Queries5319 / 6462
- Prefix Sum Queries4274 / 4682
- Pizzeria Queries3492 / 3623
- Subarray Sum Queries4442 / 4973
- Distinct Values Queries4168 / 5082
- Increasing Array Queries1506 / 1737
- Forest Queries II2863 / 3102
- Range Updates and Sums3430 / 4202
- Polynomial Queries2622 / 3089
- Range Queries and Copies1847 / 2005
Tree Algorithms
- Subordinates17723 / 19183
- Tree Matching9901 / 11698
- Tree Diameter14662 / 15714
- Tree Distances I10879 / 11814
- Tree Distances II8917 / 9324
- Company Queries I9837 / 10426
- Company Queries II9229 / 9755
- Distance Queries8615 / 9256
- Counting Paths5147 / 5523
- Subtree Queries6360 / 6816
- Path Queries5078 / 5376
- Path Queries II1805 / 2998
- Distinct Colors4831 / 5445
- Finding a Centroid3962 / 4146
- Fixed-Length Paths I1659 / 2378
- Fixed-Length Paths II680 / 1611
Mathematics
- Josephus Queries2573 / 3253
- Exponentiation14924 / 16144
- Exponentiation II10688 / 13166
- Counting Divisors12890 / 14769
- Common Divisors8642 / 10378
- Sum of Divisors4916 / 7539
- Divisor Analysis3199 / 4273
- Prime Multiples3477 / 4127
- Counting Coprime Pairs2192 / 2597
- Binomial Coefficients6035 / 6843
- Creating Strings II5066 / 5424
- Distributing Apples4948 / 5373
- Christmas Party3827 / 4164
- Bracket Sequences I2603 / 2889
- Bracket Sequences II1341 / 1550
- Counting Necklaces1297 / 1414
- Counting Grids1045 / 1118
- Fibonacci Numbers4418 / 5692
- Throwing Dice2398 / 2607
- Graph Paths I2188 / 2361
- Graph Paths II1834 / 1925
- Dice Probability2088 / 2217
- Moving Robots1046 / 1117
- Candy Lottery1613 / 1659
- Inversion Probability476 / 1443
- Stick Game2145 / 2206
- Nim Game I2709 / 2828
- Nim Game II2209 / 2310
- Stair Game1517 / 1665
- Grundy's Game977 / 1265
- Another Game1114 / 1216
String Algorithms
- Word Combinations3170 / 4868
- String Matching6342 / 9100
- Finding Borders4661 / 5223
- Finding Periods3192 / 3632
- Minimal Rotation1592 / 2607
- Longest Palindrome2414 / 3380
- Required Substring944 / 1530
- Palindrome Queries1163 / 1396
- Finding Patterns1006 / 1484
- Counting Patterns905 / 1199
- Pattern Positions800 / 1022
- Distinct Substrings955 / 1152
- Repeating Substring971 / 1095
- String Functions925 / 977
- Substring Order I686 / 737
- Substring Order II448 / 569
- Substring Distribution622 / 681
Geometry
- Point Location Test4217 / 4857
- Line Segment Intersection2559 / 3338
- Polygon Area3068 / 3299
- Point in Polygon1685 / 2149
- Polygon Lattice Points1438 / 1495
- Minimum Euclidean Distance1311 / 1796
- Convex Hull2125 / 2581
Advanced Techniques
- Meet in the Middle3637 / 5604
- Hamming Distance1995 / 2163
- Beautiful Subgrids1406 / 1582
- Reachable Nodes1423 / 1546
- Reachability Queries983 / 1165
- Cut and Paste931 / 1050
- Substring Reversals818 / 900
- Reversals and Sums818 / 895
- Necessary Roads1224 / 1261
- Necessary Cities1140 / 1199
- Eulerian Subgraphs515 / 545
- Monster Game I744 / 818
- Monster Game II665 / 722
- Subarray Squares736 / 868
- Houses and Schools482 / 556
- Knuth Division563 / 637
- Apples and Bananas523 / 581
- One Bit Positions499 / 556
- Signal Processing465 / 509
- New Roads Queries1218 / 1486
- Dynamic Connectivity560 / 640
- Parcel Delivery445 / 507
- Task Assignment426 / 464
- Distinct Routes II352 / 411
Additional Problems
- Shortest Subsequence2014 / 2585
- Counting Bits2293 / 2966
- Swap Game1257 / 1617
- Prüfer Code885 / 981
- Acyclic Graph Edges1381 / 1476
- Strongly Connected Edges866 / 953
- Even Outdegree Edges790 / 920
- Multiplication Table2989 / 3415
- Advertisement2576 / 2748
- Special Substrings591 / 640
- Permutation Inversions633 / 703
- Maximum Xor Subarray1477 / 1619
- Movie Festival Queries651 / 729
- Chess Tournament735 / 841
- Tree Traversals705 / 792
- Network Renovation622 / 826
- Graph Girth1910 / 2231
- Intersection Points1168 / 1257
- Inverse Inversions640 / 671
- Monotone Subsequences434 / 483
- String Reorder513 / 567
- Stack Weights374 / 438
- Pyramid Array499 / 593
- Increasing Subsequence II1483 / 1608
- String Removals641 / 697
- Bit Inversions1505 / 1753
- Xor Pyramid789 / 1006
- Writing Numbers510 / 554
- String Transform329 / 409
- Letter Pair Move Game118 / 174
- Maximum Building I1343 / 1410
- Sorting Methods536 / 574
- Cyclic Array672 / 773
- List of Sums302 / 405
- Increasing Array II510 / 581
- Food Division369 / 437
- Bit Problem977 / 1055
- Swap Round Sorting286 / 356
- Binary Subsequences150 / 237
- Tree Isomorphism I665 / 773
- Counting Sequences384 / 415
- Critical Cities253 / 401
- School Excursion874 / 933
- Coin Grid471 / 563
- Robot Path198 / 343
- Programmers and Artists317 / 407
- Course Schedule II1036 / 1470
- Removing Digits II127 / 273
- Coin Arrangement215 / 285
- Counting Bishops227 / 256
- Grid Puzzle I334 / 365
- Grid Puzzle II245 / 275
- Empty String932 / 1123
- Grid Paths507 / 631
- Bit Substrings235 / 293
- Reversal Sorting219 / 267
- Counting Reorders133 / 201
- Book Shop II661 / 753
- Network Breakdown625 / 666
- Visiting Cities461 / 601
- Missing Coin Sum Queries255 / 341
- Number Grid596 / 715
- Maximum Building II295 / 363
- Filling Trominos128 / 219
- Stick Divisions2383 / 2825
- Coding Company904 / 1152
- Flight Route Requests294 / 358
- Two Stacks Sorting95 / 328
- Tree Isomorphism II546 / 636
- Forbidden Cities455 / 596
- Area of Rectangles691 / 779
- Grid Completion132 / 176
- Creating Offices258 / 337
- Permutations II582 / 666
- Functional Graph Distribution146 / 184
- New Flight Routes205 / 496
- Grid Path Construction66 / 240