General
Introductory Problems
- Weird Algorithm163913 / 171425
- Missing Number141499 / 148136
- Repetitions123071 / 127863
- Increasing Array115830 / 119818
- Permutations101705 / 104709
- Number Spiral71946 / 78235
- Two Knights55209 / 56908
- Two Sets60071 / 64471
- Bit Strings68656 / 72382
- Trailing Zeros63690 / 67653
- Coin Piles56514 / 61667
- Palindrome Reorder52534 / 55386
- Gray Code35521 / 39770
- Tower of Hanoi32996 / 34295
- Creating Strings44333 / 45448
- Apple Division44752 / 50407
- Chessboard and Queens27041 / 27518
- Raab Game I5809 / 6592
- Mex Grid Construction5651 / 5963
- Knight Moves Grid5688 / 5813
- Grid Coloring I4755 / 4920
- Digit Queries19054 / 22021
- String Reorder4312 / 4988
- Grid Path Description10581 / 13683
Sorting and Searching
- Distinct Numbers81037 / 87436
- Apartments60518 / 66898
- Ferris Wheel58059 / 62415
- Concert Tickets46571 / 54012
- Restaurant Customers47379 / 51026
- Movie Festival45827 / 48452
- Sum of Two Values53343 / 59537
- Maximum Subarray Sum51236 / 53449
- Stick Lengths45773 / 47822
- Missing Coin Sum34731 / 35969
- Collecting Numbers35569 / 37977
- Collecting Numbers II15143 / 19163
- Playlist35567 / 40492
- Towers35604 / 38089
- Traffic Lights27653 / 30860
- Distinct Values Subarrays7782 / 8984
- Distinct Values Subsequences5942 / 6555
- Josephus Problem I21265 / 23356
- Josephus Problem II11561 / 15891
- Nested Ranges Check12465 / 14237
- Nested Ranges Count8382 / 9857
- Room Allocation20824 / 23819
- Factory Machines30071 / 32643
- Tasks and Deadlines24006 / 24503
- Reading Books19425 / 20791
- Sum of Three Values28336 / 31299
- Sum of Four Values17636 / 19557
- Nearest Smaller Values23687 / 24487
- Subarray Sums I31422 / 33445
- Subarray Sums II28584 / 33765
- Subarray Divisibility25869 / 28113
- Distinct Values Subarrays II15695 / 17171
- Array Division24571 / 25819
- Movie Festival II13174 / 15847
- Maximum Subarray Sum II12249 / 14562
Dynamic Programming
- Dice Combinations84401 / 89212
- Minimizing Coins72938 / 78246
- Coin Combinations I66680 / 72036
- Coin Combinations II56423 / 63650
- Removing Digits62723 / 63973
- Grid Paths I59020 / 60657
- Book Shop52881 / 58008
- Array Description38949 / 43153
- Counting Towers23826 / 25230
- Edit Distance38994 / 41136
- Longest Common Subsequence11146 / 11556
- Rectangle Cutting32126 / 35028
- Minimal Grid Path4926 / 8660
- Money Sums38014 / 39430
- Removal Game22961 / 30339
- Two Sets II29895 / 32109
- Mountain Range3425 / 6146
- Increasing Subsequence30526 / 34239
- Projects21202 / 23640
- Elevator Rides13612 / 17037
- Counting Tilings7993 / 8693
- Counting Numbers11443 / 12816
- Increasing Subsequence II5004 / 5821
Graph Algorithms
- Counting Rooms58307 / 61183
- Labyrinth40655 / 48373
- Building Roads50806 / 52610
- Message Route43797 / 45499
- Building Teams41376 / 43550
- Round Trip32692 / 35524
- Monsters22703 / 26569
- Shortest Routes I36086 / 39643
- Shortest Routes II29144 / 32581
- High Score18031 / 25035
- Flight Discount23304 / 27117
- Cycle Finding16458 / 20021
- Flight Routes15974 / 17788
- Round Trip II18013 / 20171
- Course Schedule24000 / 25297
- Longest Flight Route17119 / 20993
- Game Routes18906 / 20182
- Investigation14107 / 15131
- Planets Queries I12219 / 14271
- Planets Queries II4448 / 5599
- Planets Cycles7480 / 8326
- Road Reparation18549 / 19317
- Road Construction20413 / 21061
- Flight Routes Check16168 / 17487
- Planets and Kingdoms13059 / 13578
- Giant Pizza5469 / 6001
- Coin Collector8567 / 9449
- Mail Delivery7018 / 7663
- De Bruijn Sequence3718 / 3890
- Teleporters Path5387 / 6123
- Hamiltonian Flights8140 / 9258
- Knight's Tour3088 / 3727
- Download Speed5402 / 7163
- Police Chase4312 / 4822
- School Dance4742 / 5007
- Distinct Routes3342 / 4345
Range Queries
- Static Range Sum Queries40787 / 42611
- Static Range Minimum Queries28276 / 30268
- Dynamic Range Sum Queries29361 / 30644
- Dynamic Range Minimum Queries26561 / 27191
- Range Xor Queries27343 / 27716
- Range Update Queries21836 / 23380
- Forest Queries22381 / 23179
- Hotel Queries15856 / 16786
- List Removals13161 / 13818
- Salary Queries9997 / 12514
- Prefix Sum Queries8495 / 9164
- Pizzeria Queries6824 / 7069
- Visible Buildings Queries1811 / 1975
- Range Interval Queries1397 / 1879
- Subarray Sum Queries7972 / 8625
- Subarray Sum Queries II2021 / 2089
- Distinct Values Queries7505 / 9178
- Distinct Values Queries II1171 / 1330
- Increasing Array Queries2885 / 3295
- Movie Festival Queries1538 / 1703
- Forest Queries II4752 / 5101
- Range Updates and Sums6510 / 7684
- Polynomial Queries4811 / 5646
- Range Queries and Copies3422 / 3652
- Missing Coin Sum Queries798 / 1039
Tree Algorithms
- Subordinates33327 / 35653
- Tree Matching18988 / 22005
- Tree Diameter27189 / 28793
- Tree Distances I20860 / 22396
- Tree Distances II17012 / 17797
- Company Queries I18974 / 19965
- Company Queries II17751 / 18679
- Distance Queries16055 / 17216
- Counting Paths10092 / 10679
- Subtree Queries12111 / 12887
- Path Queries9742 / 10304
- Path Queries II4073 / 6050
- Distinct Colors9392 / 10323
- Finding a Centroid7588 / 7892
- Fixed-Length Paths I3744 / 4765
- Fixed-Length Paths II1779 / 3189
Mathematics
- Josephus Queries5256 / 6618
- Exponentiation26401 / 28145
- Exponentiation II18495 / 22055
- Counting Divisors24110 / 27184
- Common Divisors15593 / 18031
- Sum of Divisors8786 / 13019
- Divisor Analysis6025 / 8022
- Prime Multiples7000 / 8142
- Counting Coprime Pairs4625 / 5348
- Next Prime2184 / 2501
- Binomial Coefficients11244 / 12440
- Creating Strings II9374 / 9880
- Distributing Apples8938 / 9603
- Christmas Party7344 / 7853
- Permutation Order1038 / 1061
- Permutation Rounds1450 / 1613
- Bracket Sequences I4966 / 5400
- Bracket Sequences II2624 / 2995
- Counting Necklaces2410 / 2604
- Counting Grids2008 / 2132
- Fibonacci Numbers7488 / 9357
- Throwing Dice3909 / 4244
- Graph Paths I3769 / 4032
- Graph Paths II3150 / 3298
- System of Linear Equations524 / 572
- Sum of Four Squares761 / 891
- Triangle Number Sums652 / 789
- Dice Probability3342 / 3598
- Moving Robots1739 / 1836
- Candy Lottery1674 / 3290
- Inversion Probability478 / 2447
- Stick Game3814 / 3904
- Nim Game I5091 / 5275
- Nim Game II4023 / 4180
- Stair Game2743 / 2975
- Grundy's Game1906 / 2494
- Another Game2156 / 2320
String Algorithms
- Word Combinations6480 / 9280
- String Matching12477 / 16606
- Finding Borders9155 / 9997
- Finding Periods6501 / 7349
- Minimal Rotation3182 / 4769
- Longest Palindrome4771 / 6263
- All Palindromes717 / 814
- Required Substring1843 / 2764
- Palindrome Queries2243 / 2612
- Finding Patterns2118 / 2965
- Counting Patterns2005 / 2469
- Pattern Positions1688 / 2046
- Distinct Substrings1905 / 2262
- Distinct Subsequences1208 / 1282
- Repeating Substring2055 / 2374
- String Functions1800 / 1885
- Inverse Suffix Array277 / 325
- String Transform597 / 717
- Substring Order I1311 / 1455
- Substring Order II871 / 1128
- Substring Distribution1211 / 1313
Geometry
- Point Location Test7980 / 8885
- Line Segment Intersection4736 / 5919
- Polygon Area5461 / 5767
- Point in Polygon3018 / 3829
- Polygon Lattice Points2536 / 2619
- Minimum Euclidean Distance2187 / 3090
- Convex Hull3663 / 4363
- Maximum Manhattan Distances663 / 686
- All Manhattan Distances660 / 718
- Intersection Points2159 / 2329
- Line Segments Trace I367 / 381
- Line Segments Trace II305 / 323
- Lines and Queries I420 / 438
- Lines and Queries II363 / 375
- Area of Rectangles1246 / 1391
- Robot Path334 / 620
Advanced Techniques
- Meet in the Middle7256 / 9970
- Hamming Distance3427 / 3749
- Corner Subgrid Check370 / 565
- Corner Subgrid Count2369 / 2665
- Reachable Nodes2444 / 2626
- Reachability Queries1635 / 1922
- Cut and Paste1670 / 1849
- Substring Reversals1456 / 1577
- Reversals and Sums1478 / 1583
- Necessary Roads2141 / 2197
- Necessary Cities1992 / 2083
- Eulerian Subgraphs861 / 905
- Monster Game I1261 / 1402
- Monster Game II1121 / 1198
- Subarray Squares1575 / 1840
- Houses and Schools850 / 1015
- Knuth Division1030 / 1160
- Apples and Bananas1179 / 1280
- One Bit Positions915 / 997
- Signal Processing881 / 943
- New Roads Queries2401 / 2902
- Dynamic Connectivity1101 / 1238
- Parcel Delivery845 / 929
- Task Assignment982 / 1056
- Distinct Routes II642 / 729
Sliding Window Problems
- Sliding Window Sum6131 / 6359
- Sliding Window Minimum4571 / 5223
- Sliding Window Xor4494 / 4557
- Sliding Window Or1986 / 3382
- Sliding Window Distinct Values3077 / 3744
- Sliding Window Mode2475 / 2633
- Sliding Window Mex2303 / 2432
- Sliding Window Median14371 / 16394
- Sliding Window Cost9405 / 10843
- Sliding Window Inversions1286 / 1363
- Sliding Window Advertisement244 / 390
Interactive Problems
- Hidden Integer2429 / 2527
- Hidden Permutation1039 / 1215
- K-th Highest Score460 / 559
- Permuted Binary Strings563 / 577
- Colored Chairs515 / 543
- Inversion Sorting292 / 327
Bitwise Operations
- Counting Bits5421 / 7006
- Maximum Xor Subarray3221 / 3681
- Maximum Xor Subset1086 / 1187
- Number of Subset Xors953 / 973
- K Subset Xors482 / 575
- All Subarray Xors294 / 481
- Xor Pyramid Peak2177 / 2630
- Xor Pyramid Diagonal340 / 380
- Xor Pyramid Row293 / 344
- SOS Bit Problem2289 / 2430
- And Subset Count458 / 476
Construction Problems
- Inverse Inversions1787 / 1903
- Monotone Subsequences1081 / 1273
- Third Permutation439 / 530
- Permutation Prime Sums438 / 473
- Chess Tournament1264 / 1463
- Distinct Sums Grid139 / 215
- Filling Trominos247 / 448
- Grid Path Construction124 / 443
Advanced Graph Problems
- Nearest Shops759 / 979
- Prüfer Code1604 / 1722
- Tree Traversals1299 / 1431
- Course Schedule II2048 / 2924
- Acyclic Graph Edges2310 / 2446
- Strongly Connected Edges1588 / 1870
- Even Outdegree Edges1445 / 1682
- Graph Girth3606 / 4089
- Fixed Length Walk Queries379 / 420
- Transfer Speeds Sum441 / 455
- MST Edge Check681 / 740
- MST Edge Set Check259 / 293
- MST Edge Cost412 / 431
- Network Breakdown1227 / 1335
- Tree Coin Collecting I366 / 398
- Tree Coin Collecting II198 / 231
- Tree Isomorphism I1142 / 1356
- Tree Isomorphism II938 / 1081
- Flight Route Requests524 / 645
- Critical Cities448 / 687
- Visiting Cities714 / 939
- Graph Coloring239 / 279
- Bus Companies282 / 290
- Split into Two Paths101 / 185
- Network Renovation970 / 1288
- Forbidden Cities881 / 1150
- Creating Offices437 / 571
- New Flight Routes347 / 925
Counting Problems
- Filled Subgrid Count I618 / 694
- Filled Subgrid Count II335 / 412
- All Letter Subgrid Count I187 / 280
- All Letter Subgrid Count II147 / 187
- Border Subgrid Count I100 / 173
- Border Subgrid Count II109 / 128
- Raab Game II112 / 129
- Empty String1768 / 2148
- Permutation Inversions1072 / 1183
- Counting Bishops413 / 460
- Counting Sequences701 / 755
- Grid Paths II798 / 999
- Counting Permutations929 / 1048
- Grid Completion234 / 298
- Counting Reorders258 / 368
- Tournament Graph Distribution112 / 119
- Collecting Numbers Distribution122 / 130
- Functional Graph Distribution254 / 313
Additional Problems I
- Shortest Subsequence3098 / 4076
- Distinct Values Sum704 / 728
- Distinct Values Splits506 / 538
- Swap Game2108 / 2710
- Beautiful Permutation II573 / 870
- Multiplication Table7151 / 7964
- Bubble Sort Rounds I430 / 490
- Bubble Sort Rounds II286 / 322
- Nearest Campsites I190 / 221
- Nearest Campsites II187 / 200
- Advertisement4574 / 4844
- Special Substrings1014 / 1113
- Counting LCM Arrays286 / 312
- Square Subsets232 / 257
- Subarray Sum Constraints433 / 461
- Water Containers Moves185 / 195
- Water Containers Queries219 / 230
- Stack Weights613 / 730
- Maximum Average Subarrays179 / 197
- Subsets with Fixed Average221 / 240
- Two Array Average219 / 246
- Pyramid Array791 / 956
- Permutation Subsequence270 / 278
- Bit Inversions2416 / 2730
- Writing Numbers765 / 826
- Letter Pair Move Game211 / 291
- Maximum Building I2157 / 2249
- Sorting Methods799 / 853
- Cyclic Array1255 / 1427
- List of Sums509 / 659
Additional Problems II
- Bouncing Ball Steps243 / 269
- Bouncing Ball Cycle95 / 134
- Knight Moves Queries123 / 147
- K Subset Sums I198 / 254
- K Subset Sums II110 / 145
- Increasing Array II841 / 958
- Food Division539 / 647
- Swap Round Sorting428 / 527
- Binary Subsequences297 / 433
- School Excursion1436 / 1519
- Coin Grid930 / 1085
- Grid Coloring II144 / 187
- Programmers and Artists524 / 734
- Removing Digits II220 / 480
- Coin Arrangement344 / 460
- Replace with Difference135 / 161
- Grid Puzzle I563 / 616
- Grid Puzzle II543 / 595
- Bit Substrings411 / 498
- Reversal Sorting366 / 443
- Book Shop II1294 / 1472
- GCD Subsets427 / 439
- Minimum Cost Pairs148 / 193
- Same Sum Subsets119 / 234
- Mex Grid Queries877 / 1027
- Maximum Building II461 / 568
- Stick Divisions3926 / 4595
- Stick Difference65 / 266
- Coding Company1559 / 2039
- Two Stacks Sorting184 / 593