General
Introductory Problems
- Weird Algorithm176891 / 184761
- Missing Number152600 / 159501
- Repetitions132629 / 137610
- Increasing Array125028 / 129164
- Permutations109542 / 112695
- Number Spiral77854 / 84396
- Two Knights60055 / 61819
- Two Sets65289 / 69843
- Bit Strings74255 / 78138
- Trailing Zeros68754 / 72908
- Coin Piles61175 / 66534
- Palindrome Reorder56861 / 59811
- Gray Code38859 / 43328
- Tower of Hanoi36232 / 37613
- Creating Strings47969 / 49129
- Apple Division48692 / 54549
- Chessboard and Queens29638 / 30136
- Raab Game I7771 / 8703
- Mex Grid Construction7539 / 7900
- Knight Moves Grid7605 / 7771
- Grid Coloring I6392 / 6615
- Digit Queries20820 / 23848
- String Reorder5714 / 6521
- Grid Path Description11669 / 14933
Sorting and Searching
- Distinct Numbers87966 / 94632
- Apartments66137 / 72706
- Ferris Wheel63733 / 68251
- Concert Tickets51124 / 58932
- Restaurant Customers52017 / 55832
- Movie Festival50577 / 53309
- Sum of Two Values58445 / 64924
- Maximum Subarray Sum55783 / 58061
- Stick Lengths49980 / 52102
- Missing Coin Sum38274 / 39572
- Collecting Numbers39196 / 41716
- Collecting Numbers II17261 / 21464
- Playlist39121 / 44276
- Towers39092 / 41694
- Traffic Lights30448 / 33824
- Distinct Values Subarrays10532 / 11778
- Distinct Values Subsequences8119 / 8829
- Josephus Problem I23733 / 25925
- Josephus Problem II12921 / 17682
- Nested Ranges Check14159 / 15992
- Nested Ranges Count9472 / 11064
- Room Allocation23097 / 26269
- Factory Machines33501 / 36150
- Tasks and Deadlines26716 / 27232
- Reading Books21688 / 23131
- Sum of Three Values31202 / 34267
- Sum of Four Values19497 / 21503
- Nearest Smaller Values26145 / 26978
- Subarray Sums I34694 / 36769
- Subarray Sums II31650 / 37066
- Subarray Divisibility28640 / 30972
- Distinct Values Subarrays II17530 / 19046
- Array Division27134 / 28437
- Movie Festival II14753 / 17562
- Maximum Subarray Sum II13769 / 16212
Dynamic Programming
- Dice Combinations92485 / 97585
- Minimizing Coins80030 / 85658
- Coin Combinations I73125 / 78761
- Coin Combinations II62026 / 69644
- Removing Digits68965 / 70348
- Grid Paths I64749 / 66462
- Book Shop58398 / 63800
- Array Description43314 / 47727
- Counting Towers27003 / 28498
- Edit Distance43078 / 45296
- Longest Common Subsequence15138 / 15635
- Rectangle Cutting35592 / 38656
- Minimal Grid Path7068 / 11680
- Money Sums41960 / 43435
- Removal Game26082 / 33601
- Two Sets II33158 / 35448
- Mountain Range4887 / 8335
- Increasing Subsequence33649 / 37572
- Projects23704 / 26257
- Elevator Rides15570 / 19253
- Counting Tilings9118 / 9856
- Counting Numbers13644 / 15085
- Increasing Subsequence II6137 / 7193
Graph Algorithms
- Counting Rooms64334 / 67327
- Labyrinth45744 / 53724
- Building Roads56351 / 58222
- Message Route48869 / 50632
- Building Teams46114 / 48338
- Round Trip36574 / 39534
- Monsters25998 / 30012
- Shortest Routes I40382 / 44020
- Shortest Routes II32632 / 36220
- High Score20976 / 28248
- Flight Discount26881 / 30847
- Cycle Finding18958 / 22635
- Flight Routes18495 / 20406
- Round Trip II20510 / 22754
- Course Schedule27069 / 28382
- Longest Flight Route19866 / 23883
- Game Routes21645 / 22966
- Investigation16438 / 17529
- Planets Queries I14250 / 16423
- Planets Queries II5173 / 6418
- Planets Cycles8604 / 9502
- Road Reparation21076 / 21889
- Road Construction22987 / 23674
- Flight Routes Check18269 / 19636
- Planets and Kingdoms14879 / 15490
- Giant Pizza6267 / 6839
- Coin Collector9889 / 10811
- Mail Delivery7872 / 8541
- De Bruijn Sequence4147 / 4333
- Teleporters Path6110 / 6865
- Hamiltonian Flights9327 / 10545
- Knight's Tour3483 / 4164
- Download Speed6067 / 7892
- Police Chase4849 / 5379
- School Dance5319 / 5605
- Distinct Routes3756 / 4807
Range Queries
- Static Range Sum Queries45026 / 47002
- Static Range Minimum Queries30926 / 33095
- Dynamic Range Sum Queries32187 / 33552
- Dynamic Range Minimum Queries29063 / 29735
- Range Xor Queries29671 / 30059
- Range Update Queries24016 / 25635
- Forest Queries24658 / 25495
- Hotel Queries17500 / 18463
- List Removals14553 / 15238
- Salary Queries11255 / 13907
- Prefix Sum Queries9429 / 10128
- Pizzeria Queries7526 / 7781
- Visible Buildings Queries2304 / 2503
- Range Interval Queries1760 / 2335
- Subarray Sum Queries8683 / 9363
- Subarray Sum Queries II2600 / 2678
- Distinct Values Queries8243 / 9967
- Distinct Values Queries II1456 / 1653
- Increasing Array Queries3125 / 3554
- Movie Festival Queries1746 / 1919
- Forest Queries II5110 / 5465
- Range Updates and Sums7198 / 8415
- Polynomial Queries5284 / 6157
- Range Queries and Copies3721 / 3963
- Missing Coin Sum Queries882 / 1204
Tree Algorithms
- Subordinates37014 / 39487
- Tree Matching21428 / 24653
- Tree Diameter30300 / 31968
- Tree Distances I23545 / 25150
- Tree Distances II19184 / 20023
- Company Queries I21565 / 22615
- Company Queries II20171 / 21161
- Distance Queries18191 / 19415
- Counting Paths11503 / 12122
- Subtree Queries13506 / 14337
- Path Queries10890 / 11477
- Path Queries II4577 / 6686
- Distinct Colors10438 / 11405
- Finding a Centroid8497 / 8824
- Fixed-Length Paths I4250 / 5325
- Fixed-Length Paths II2088 / 3607
Mathematics
- Josephus Queries5887 / 7331
- Exponentiation28638 / 30457
- Exponentiation II19991 / 23696
- Counting Divisors26343 / 29632
- Common Divisors16930 / 19500
- Sum of Divisors9661 / 14085
- Divisor Analysis6628 / 8744
- Prime Multiples7700 / 8893
- Counting Coprime Pairs5093 / 5860
- Next Prime2726 / 3099
- Binomial Coefficients12331 / 13591
- Creating Strings II10202 / 10737
- Distributing Apples9748 / 10455
- Christmas Party8113 / 8642
- Permutation Order1304 / 1339
- Permutation Rounds1906 / 2097
- Bracket Sequences I5425 / 5878
- Bracket Sequences II2892 / 3283
- Counting Necklaces2624 / 2833
- Counting Grids2209 / 2343
- Fibonacci Numbers8057 / 10009
- Throwing Dice4255 / 4603
- Graph Paths I4130 / 4398
- Graph Paths II3462 / 3622
- System of Linear Equations660 / 715
- Sum of Four Squares940 / 1125
- Triangle Number Sums823 / 984
- Dice Probability3650 / 3917
- Moving Robots1891 / 1991
- Candy Lottery1974 / 3637
- Inversion Probability591 / 2682
- Stick Game4158 / 4255
- Nim Game I5559 / 5761
- Nim Game II4403 / 4571
- Stair Game2978 / 3224
- Grundy's Game2084 / 2725
- Another Game2358 / 2532
String Algorithms
- Word Combinations7189 / 10158
- String Matching13660 / 17991
- Finding Borders10073 / 10951
- Finding Periods7202 / 8096
- Minimal Rotation3600 / 5243
- Longest Palindrome5293 / 6852
- All Palindromes973 / 1087
- Required Substring2020 / 2987
- Palindrome Queries2469 / 2845
- Finding Patterns2345 / 3237
- Counting Patterns2230 / 2711
- Pattern Positions1883 / 2256
- Distinct Substrings2104 / 2487
- Distinct Subsequences1354 / 1431
- Repeating Substring2273 / 2601
- String Functions1992 / 2086
- Inverse Suffix Array381 / 435
- String Transform688 / 813
- Substring Order I1436 / 1584
- Substring Order II978 / 1247
- Substring Distribution1337 / 1445
Geometry
- Point Location Test8604 / 9537
- Line Segment Intersection5102 / 6331
- Polygon Area5854 / 6171
- Point in Polygon3284 / 4118
- Polygon Lattice Points2667 / 2850
- Minimum Euclidean Distance2365 / 3293
- Convex Hull3916 / 4636
- Maximum Manhattan Distances853 / 886
- All Manhattan Distances892 / 978
- Intersection Points2326 / 2503
- Line Segments Trace I468 / 483
- Line Segments Trace II390 / 409
- Lines and Queries I512 / 537
- Lines and Queries II456 / 477
- Area of Rectangles1373 / 1526
- Robot Path376 / 685
Advanced Techniques
- Meet in the Middle8318 / 11150
- Hamming Distance3666 / 4005
- Corner Subgrid Check326 / 699
- Corner Subgrid Count2499 / 2839
- Reachable Nodes2608 / 2792
- Reachability Queries1750 / 2046
- Cut and Paste1802 / 1989
- Substring Reversals1591 / 1716
- Reversals and Sums1617 / 1726
- Necessary Roads2324 / 2383
- Necessary Cities2159 / 2253
- Eulerian Subgraphs923 / 972
- Monster Game I1383 / 1530
- Monster Game II1220 / 1301
- Subarray Squares1728 / 2000
- Houses and Schools939 / 1110
- Knuth Division1125 / 1260
- Apples and Bananas1314 / 1419
- One Bit Positions993 / 1079
- Signal Processing977 / 1042
- New Roads Queries2620 / 3142
- Dynamic Connectivity1199 / 1339
- Parcel Delivery949 / 1035
- Task Assignment1093 / 1179
- Distinct Routes II723 / 814
Sliding Window Problems
- Sliding Window Sum8028 / 8286
- Sliding Window Minimum6038 / 6870
- Sliding Window Xor5900 / 5976
- Sliding Window Or2650 / 4382
- Sliding Window Distinct Values4211 / 4904
- Sliding Window Mode3277 / 3468
- Sliding Window Mex3089 / 3249
- Sliding Window Median15284 / 17364
- Sliding Window Cost9978 / 11462
- Sliding Window Inversions1654 / 1749
- Sliding Window Advertisement320 / 503
Interactive Problems
- Hidden Integer2897 / 3019
- Hidden Permutation1302 / 1506
- K-th Highest Score594 / 717
- Permuted Binary Strings695 / 714
- Colored Chairs655 / 694
- Inversion Sorting383 / 431
Bitwise Operations
- Counting Bits6230 / 7997
- Maximum Xor Subarray3679 / 4203
- Maximum Xor Subset1385 / 1521
- Number of Subset Xors1205 / 1233
- K Subset Xors631 / 741
- All Subarray Xors380 / 586
- Xor Pyramid Peak2447 / 2928
- Xor Pyramid Diagonal433 / 485
- Xor Pyramid Row373 / 437
- SOS Bit Problem2586 / 2739
- And Subset Count614 / 638
Construction Problems
- Inverse Inversions2066 / 2205
- Monotone Subsequences1251 / 1477
- Third Permutation555 / 683
- Permutation Prime Sums560 / 600
- Chess Tournament1389 / 1600
- Distinct Sums Grid198 / 295
- Filling Trominos308 / 530
- Grid Path Construction170 / 499
Advanced Graph Problems
- Nearest Shops957 / 1228
- Prüfer Code1726 / 1849
- Tree Traversals1420 / 1553
- Course Schedule II2354 / 3292
- Acyclic Graph Edges2456 / 2603
- Strongly Connected Edges1792 / 2080
- Even Outdegree Edges1579 / 1832
- Graph Girth3978 / 4485
- Fixed Length Walk Queries478 / 529
- Transfer Speeds Sum537 / 554
- MST Edge Check880 / 952
- MST Edge Set Check326 / 368
- MST Edge Cost520 / 541
- Network Breakdown1343 / 1458
- Tree Coin Collecting I456 / 495
- Tree Coin Collecting II260 / 297
- Tree Isomorphism I1230 / 1453
- Tree Isomorphism II1023 / 1169
- Flight Route Requests581 / 718
- Critical Cities504 / 753
- Visiting Cities767 / 1002
- Graph Coloring296 / 345
- Bus Companies343 / 353
- Split into Two Paths139 / 237
- Network Renovation1036 / 1359
- Forbidden Cities977 / 1262
- Creating Offices475 / 617
- New Flight Routes410 / 1040
Counting Problems
- Filled Subgrid Count I787 / 876
- Filled Subgrid Count II421 / 520
- All Letter Subgrid Count I240 / 344
- All Letter Subgrid Count II151 / 228
- Border Subgrid Count I128 / 218
- Border Subgrid Count II142 / 164
- Raab Game II145 / 165
- Empty String1922 / 2330
- Permutation Inversions1140 / 1255
- Counting Bishops445 / 498
- Counting Sequences766 / 821
- Grid Paths II850 / 1070
- Counting Permutations982 / 1107
- Grid Completion260 / 329
- Counting Reorders297 / 412
- Tournament Graph Distribution145 / 155
- Collecting Numbers Distribution153 / 160
- Functional Graph Distribution279 / 342
Additional Problems I
- Shortest Subsequence3271 / 4272
- Distinct Values Sum867 / 891
- Distinct Values Splits611 / 655
- Swap Game2260 / 2885
- Beautiful Permutation II761 / 1166
- Multiplication Table7818 / 8670
- Bubble Sort Rounds I554 / 626
- Bubble Sort Rounds II383 / 426
- Nearest Campsites I239 / 280
- Nearest Campsites II232 / 250
- Advertisement4918 / 5199
- Special Substrings1086 / 1189
- Counting LCM Arrays370 / 402
- Square Subsets286 / 315
- Subarray Sum Constraints583 / 621
- Water Containers Moves228 / 242
- Water Containers Queries264 / 279
- Stack Weights652 / 779
- Maximum Average Subarrays228 / 250
- Subsets with Fixed Average268 / 291
- Two Array Average273 / 304
- Pyramid Array862 / 1037
- Permutation Subsequence316 / 327
- Bit Inversions2567 / 2887
- Writing Numbers810 / 877
- Letter Pair Move Game235 / 325
- Maximum Building I2279 / 2379
- Sorting Methods845 / 902
- Cyclic Array1372 / 1546
- List of Sums544 / 703
Additional Problems II
- Bouncing Ball Steps316 / 348
- Bouncing Ball Cycle133 / 180
- Knight Moves Queries161 / 193
- K Subset Sums I259 / 322
- K Subset Sums II154 / 193
- Increasing Array II908 / 1036
- Food Division579 / 689
- Swap Round Sorting449 / 555
- Binary Subsequences320 / 461
- School Excursion1534 / 1620
- Coin Grid1021 / 1186
- Grid Coloring II172 / 221
- Programmers and Artists563 / 780
- Removing Digits II244 / 518
- Coin Arrangement372 / 492
- Replace with Difference171 / 204
- Grid Puzzle I606 / 664
- Grid Puzzle II589 / 644
- Bit Substrings447 / 539
- Reversal Sorting394 / 474
- Book Shop II1428 / 1626
- GCD Subsets510 / 526
- Minimum Cost Pairs180 / 226
- Same Sum Subsets157 / 297
- Mex Grid Queries929 / 1084
- Maximum Building II489 / 601
- Stick Divisions4154 / 4839
- Stick Difference105 / 336
- Coding Company1658 / 2165
- Two Stacks Sorting209 / 643