General
Introductory Problems
- Weird Algorithm99790 / 104534
- Missing Number84955 / 89623
- Repetitions74202 / 77730
- Increasing Array69281 / 72197
- Permutations60927 / 63010
- Number Spiral43112 / 47025
- Two Knights32335 / 33497
- Two Sets34950 / 37991
- Bit Strings40698 / 42988
- Trailing Zeros38084 / 40738
- Coin Piles33548 / 37035
- Palindrome Reorder30665 / 32696
- Gray Code19089 / 21832
- Tower of Hanoi17795 / 18561
- Creating Strings26436 / 27242
- Apple Division25661 / 29439
- Chessboard and Queens15240 / 15557
- Digit Queries10304 / 12396
- Grid Paths6353 / 8130
Sorting and Searching
- Distinct Numbers46828 / 51334
- Apartments34149 / 38809
- Ferris Wheel32493 / 35549
- Concert Tickets26015 / 30992
- Restaurant Customers26741 / 29191
- Movie Festival25135 / 26878
- Sum of Two Values29653 / 33835
- Maximum Subarray Sum29211 / 30734
- Stick Lengths25877 / 27336
- Missing Coin Sum18091 / 18832
- Collecting Numbers18746 / 20307
- Collecting Numbers II7469 / 9784
- Playlist19429 / 22672
- Towers19926 / 21564
- Traffic Lights15619 / 17604
- Josephus Problem I10642 / 12071
- Josephus Problem II6154 / 8038
- Nested Ranges Check6045 / 7114
- Nested Ranges Count4300 / 4974
- Room Allocation11375 / 13242
- Factory Machines14731 / 16507
- Tasks and Deadlines13214 / 13529
- Reading Books10532 / 11321
- Sum of Three Values15369 / 17431
- Sum of Four Values9746 / 11023
- Nearest Smaller Values12985 / 13501
- Subarray Sums I16799 / 18094
- Subarray Sums II15523 / 17723
- Subarray Divisibility13614 / 15025
- Subarray Distinct Values7768 / 8416
- Array Division12470 / 13243
- Sliding Window Median8257 / 9446
- Sliding Window Cost5743 / 6613
- Movie Festival II7102 / 8608
- Maximum Subarray Sum II6505 / 7810
Dynamic Programming
- Dice Combinations46216 / 49252
- Minimizing Coins39776 / 43075
- Coin Combinations I36558 / 39902
- Coin Combinations II30699 / 35245
- Removing Digits33938 / 34816
- Grid Paths32261 / 33358
- Book Shop28380 / 31748
- Array Description20497 / 23130
- Counting Towers11679 / 12398
- Edit Distance21254 / 22605
- Rectangle Cutting17734 / 19464
- Money Sums21165 / 22113
- Removal Game15105 / 16811
- Two Sets II16684 / 18232
- Increasing Subsequence17153 / 19497
- Projects11526 / 13095
- Elevator Rides6981 / 8976
- Counting Tilings3990 / 4394
- Counting Numbers5372 / 6130
Graph Algorithms
- Counting Rooms31532 / 33566
- Labyrinth20682 / 25713
- Building Roads27283 / 28456
- Message Route23185 / 24321
- Building Teams22254 / 23394
- Round Trip17270 / 19083
- Monsters10902 / 13428
- Shortest Routes I18532 / 21177
- Shortest Routes II15651 / 17175
- High Score7869 / 12912
- Flight Discount10938 / 13411
- Cycle Finding8121 / 10235
- Flight Routes7550 / 8515
- Round Trip II9073 / 10425
- Course Schedule12574 / 13144
- Longest Flight Route7789 / 10457
- Game Routes9085 / 10017
- Investigation6670 / 7262
- Planets Queries I5639 / 6888
- Planets Queries II2261 / 2808
- Planets Cycles3771 / 4251
- Road Reparation9020 / 9487
- Road Construction9515 / 9893
- Flight Routes Check8092 / 8949
- Planets and Kingdoms6521 / 6806
- Giant Pizza2658 / 2992
- Coin Collector4070 / 4615
- Mail Delivery3530 / 3933
- De Bruijn Sequence1900 / 2001
- Teleporters Path2801 / 3136
- Hamiltonian Flights3914 / 4458
- Knight's Tour1652 / 1959
- Download Speed2758 / 3891
- Police Chase2216 / 2545
- School Dance2438 / 2600
- Distinct Routes1587 / 2158
Range Queries
- Static Range Sum Queries21496 / 22502
- Static Range Minimum Queries15977 / 17108
- Dynamic Range Sum Queries16469 / 17248
- Dynamic Range Minimum Queries14982 / 15394
- Range Xor Queries15133 / 15368
- Range Update Queries12073 / 13024
- Forest Queries11825 / 12314
- Hotel Queries8649 / 9147
- List Removals7211 / 7622
- Salary Queries5333 / 6479
- Prefix Sum Queries4285 / 4695
- Pizzeria Queries3501 / 3633
- Subarray Sum Queries4453 / 4982
- Distinct Values Queries4175 / 5087
- Increasing Array Queries1509 / 1740
- Forest Queries II2871 / 3113
- Range Updates and Sums3440 / 4217
- Polynomial Queries2629 / 3099
- Range Queries and Copies1851 / 2009
Tree Algorithms
- Subordinates17771 / 19234
- Tree Matching9926 / 11729
- Tree Diameter14709 / 15759
- Tree Distances I10907 / 11845
- Tree Distances II8941 / 9348
- Company Queries I9867 / 10459
- Company Queries II9259 / 9789
- Distance Queries8646 / 9285
- Counting Paths5164 / 5540
- Subtree Queries6382 / 6840
- Path Queries5095 / 5392
- Path Queries II1815 / 3007
- Distinct Colors4850 / 5465
- Finding a Centroid3971 / 4155
- Fixed-Length Paths I1668 / 2386
- Fixed-Length Paths II684 / 1614
Mathematics
- Josephus Queries2575 / 3260
- Exponentiation14962 / 16184
- Exponentiation II10721 / 13199
- Counting Divisors12923 / 14820
- Common Divisors8662 / 10405
- Sum of Divisors4928 / 7555
- Divisor Analysis3212 / 4293
- Prime Multiples3489 / 4141
- Counting Coprime Pairs2195 / 2602
- Binomial Coefficients6047 / 6857
- Creating Strings II5073 / 5433
- Distributing Apples4954 / 5381
- Christmas Party3836 / 4173
- Bracket Sequences I2611 / 2897
- Bracket Sequences II1344 / 1554
- Counting Necklaces1301 / 1418
- Counting Grids1047 / 1121
- Fibonacci Numbers4428 / 5707
- Throwing Dice2401 / 2610
- Graph Paths I2192 / 2365
- Graph Paths II1837 / 1928
- Dice Probability2092 / 2221
- Moving Robots1049 / 1120
- Candy Lottery1617 / 1663
- Inversion Probability479 / 1447
- Stick Game2153 / 2214
- Nim Game I2717 / 2838
- Nim Game II2216 / 2318
- Stair Game1527 / 1675
- Grundy's Game986 / 1273
- Another Game1122 / 1224
String Algorithms
- Word Combinations3178 / 4879
- String Matching6384 / 9141
- Finding Borders4683 / 5244
- Finding Periods3210 / 3654
- Minimal Rotation1597 / 2616
- Longest Palindrome2421 / 3391
- Required Substring946 / 1533
- Palindrome Queries1168 / 1403
- Finding Patterns1010 / 1488
- Counting Patterns910 / 1204
- Pattern Positions804 / 1027
- Distinct Substrings956 / 1154
- Repeating Substring972 / 1096
- String Functions928 / 981
- Substring Order I691 / 742
- Substring Order II449 / 571
- Substring Distribution625 / 684
Geometry
- Point Location Test4227 / 4871
- Line Segment Intersection2566 / 3348
- Polygon Area3075 / 3307
- Point in Polygon1689 / 2155
- Polygon Lattice Points1442 / 1499
- Minimum Euclidean Distance1318 / 1804
- Convex Hull2131 / 2586
Advanced Techniques
- Meet in the Middle3648 / 5619
- Hamming Distance2002 / 2170
- Beautiful Subgrids1413 / 1590
- Reachable Nodes1428 / 1550
- Reachability Queries987 / 1171
- Cut and Paste935 / 1054
- Substring Reversals822 / 904
- Reversals and Sums821 / 899
- Necessary Roads1227 / 1264
- Necessary Cities1144 / 1203
- Eulerian Subgraphs515 / 545
- Monster Game I745 / 819
- Monster Game II667 / 724
- Subarray Squares736 / 868
- Houses and Schools483 / 559
- Knuth Division565 / 640
- Apples and Bananas525 / 582
- One Bit Positions501 / 558
- Signal Processing469 / 513
- New Roads Queries1224 / 1493
- Dynamic Connectivity562 / 644
- Parcel Delivery446 / 508
- Task Assignment429 / 468
- Distinct Routes II355 / 414
Additional Problems
- Shortest Subsequence2019 / 2590
- Counting Bits2304 / 2977
- Swap Game1265 / 1624
- Prüfer Code889 / 985
- Acyclic Graph Edges1385 / 1480
- Strongly Connected Edges872 / 960
- Even Outdegree Edges793 / 925
- Multiplication Table3007 / 3435
- Advertisement2583 / 2754
- Special Substrings595 / 645
- Permutation Inversions639 / 709
- Maximum Xor Subarray1483 / 1626
- Movie Festival Queries655 / 733
- Chess Tournament737 / 843
- Tree Traversals709 / 797
- Network Renovation626 / 830
- Graph Girth1919 / 2239
- Intersection Points1170 / 1259
- Inverse Inversions646 / 677
- Monotone Subsequences436 / 486
- String Reorder515 / 569
- Stack Weights375 / 439
- Pyramid Array499 / 596
- Increasing Subsequence II1486 / 1613
- String Removals645 / 701
- Bit Inversions1508 / 1757
- Xor Pyramid791 / 1008
- Writing Numbers510 / 554
- String Transform329 / 410
- Letter Pair Move Game119 / 176
- Maximum Building I1345 / 1412
- Sorting Methods538 / 577
- Cyclic Array672 / 774
- List of Sums302 / 406
- Increasing Array II511 / 583
- Food Division369 / 438
- Bit Problem980 / 1058
- Swap Round Sorting287 / 357
- Binary Subsequences150 / 238
- Tree Isomorphism I667 / 775
- Counting Sequences384 / 415
- Critical Cities258 / 403
- School Excursion874 / 933
- Coin Grid471 / 563
- Robot Path199 / 345
- Programmers and Artists317 / 407
- Course Schedule II1043 / 1479
- Removing Digits II127 / 274
- Coin Arrangement216 / 286
- Counting Bishops228 / 257
- Grid Puzzle I334 / 365
- Grid Puzzle II246 / 276
- Empty String935 / 1126
- Grid Paths508 / 633
- Bit Substrings236 / 294
- Reversal Sorting219 / 267
- Counting Reorders133 / 201
- Book Shop II661 / 753
- Network Breakdown627 / 667
- Visiting Cities461 / 601
- Missing Coin Sum Queries256 / 342
- Number Grid596 / 715
- Maximum Building II295 / 363
- Filling Trominos128 / 219
- Stick Divisions2391 / 2834
- Coding Company904 / 1152
- Flight Route Requests296 / 359
- Two Stacks Sorting95 / 328
- Tree Isomorphism II549 / 638
- Forbidden Cities456 / 598
- Area of Rectangles692 / 780
- Grid Completion133 / 177
- Creating Offices259 / 337
- Permutations II583 / 667
- Functional Graph Distribution146 / 184
- New Flight Routes205 / 496
- Grid Path Construction67 / 241