General
Introductory Problems
- Weird Algorithm183412 / 191476
- Missing Number158207 / 165297
- Repetitions137343 / 142435
- Increasing Array129608 / 133857
- Permutations113195 / 116431
- Number Spiral80534 / 87258
- Two Knights62176 / 63972
- Two Sets67529 / 72199
- Bit Strings76693 / 80677
- Trailing Zeros70992 / 75274
- Coin Piles63257 / 68737
- Palindrome Reorder58876 / 61887
- Gray Code40308 / 44883
- Tower of Hanoi37686 / 39104
- Creating Strings49581 / 50768
- Apple Division50512 / 56509
- Chessboard and Queens30748 / 31258
- Raab Game I8551 / 9523
- Mex Grid Construction8239 / 8636
- Knight Moves Grid8339 / 8528
- Grid Coloring I7038 / 7276
- Digit Queries21528 / 24580
- String Reorder6218 / 7088
- Grid Path Description12093 / 15410
Sorting and Searching
- Distinct Numbers91287 / 98141
- Apartments68487 / 75194
- Ferris Wheel66095 / 70718
- Concert Tickets53027 / 60994
- Restaurant Customers53826 / 57728
- Movie Festival52431 / 55219
- Sum of Two Values60693 / 67328
- Maximum Subarray Sum57611 / 59948
- Stick Lengths51550 / 53723
- Missing Coin Sum39592 / 40914
- Collecting Numbers40509 / 43085
- Collecting Numbers II17960 / 22235
- Playlist40523 / 45758
- Towers40422 / 43078
- Traffic Lights31429 / 34863
- Distinct Values Subarrays11524 / 12807
- Distinct Values Subsequences8865 / 9612
- Josephus Problem I24630 / 26851
- Josephus Problem II13375 / 18328
- Nested Ranges Check14734 / 16594
- Nested Ranges Count9872 / 11488
- Room Allocation23963 / 27179
- Factory Machines34953 / 37642
- Tasks and Deadlines27720 / 28239
- Reading Books22537 / 23996
- Sum of Three Values32322 / 35461
- Sum of Four Values20121 / 22160
- Nearest Smaller Values27154 / 28007
- Subarray Sums I36004 / 38119
- Subarray Sums II32934 / 38466
- Subarray Divisibility29716 / 32114
- Distinct Values Subarrays II18145 / 19673
- Array Division28154 / 29489
- Movie Festival II15354 / 18216
- Maximum Subarray Sum II14328 / 16837
Dynamic Programming
- Dice Combinations95916 / 101169
- Minimizing Coins82819 / 88577
- Coin Combinations I75645 / 81427
- Coin Combinations II64154 / 71980
- Removing Digits71364 / 72750
- Grid Paths I66971 / 68739
- Book Shop60475 / 66033
- Array Description44812 / 49291
- Counting Towers28076 / 29603
- Edit Distance44506 / 46790
- Longest Common Subsequence16523 / 17053
- Rectangle Cutting36710 / 39853
- Minimal Grid Path7847 / 12711
- Money Sums43340 / 44866
- Removal Game27116 / 34680
- Two Sets II34239 / 36545
- Mountain Range5449 / 9088
- Increasing Subsequence34773 / 38905
- Projects24600 / 27257
- Elevator Rides16248 / 19999
- Counting Tilings9524 / 10275
- Counting Numbers14276 / 15735
- Increasing Subsequence II6625 / 7745
Graph Algorithms
- Counting Rooms66721 / 69783
- Labyrinth47512 / 55582
- Building Roads58423 / 60333
- Message Route50750 / 52543
- Building Teams47875 / 50145
- Round Trip37967 / 40987
- Monsters27137 / 31196
- Shortest Routes I42016 / 45724
- Shortest Routes II33828 / 37492
- High Score21913 / 29289
- Flight Discount27988 / 32036
- Cycle Finding19805 / 23538
- Flight Routes19258 / 21182
- Round Trip II21371 / 23685
- Course Schedule28268 / 29631
- Longest Flight Route20752 / 24784
- Game Routes22538 / 23865
- Investigation17223 / 18328
- Planets Queries I14938 / 17138
- Planets Queries II5447 / 6734
- Planets Cycles9025 / 9938
- Road Reparation22057 / 22886
- Road Construction24028 / 24729
- Flight Routes Check19093 / 20476
- Planets and Kingdoms15663 / 16279
- Giant Pizza6587 / 7178
- Coin Collector10453 / 11408
- Mail Delivery8241 / 8927
- De Bruijn Sequence4334 / 4527
- Teleporters Path6371 / 7134
- Hamiltonian Flights9830 / 11073
- Knight's Tour3653 / 4349
- Download Speed6355 / 8207
- Police Chase5058 / 5595
- School Dance5600 / 5890
- Distinct Routes3926 / 4994
Range Queries
- Static Range Sum Queries46883 / 48922
- Static Range Minimum Queries32139 / 34371
- Dynamic Range Sum Queries33537 / 34936
- Dynamic Range Minimum Queries30253 / 30937
- Range Xor Queries30797 / 31196
- Range Update Queries25041 / 26688
- Forest Queries25652 / 26513
- Hotel Queries18276 / 19255
- List Removals15198 / 15896
- Salary Queries11841 / 14527
- Prefix Sum Queries9897 / 10602
- Pizzeria Queries7918 / 8179
- Visible Buildings Queries2565 / 2772
- Range Interval Queries1952 / 2578
- Subarray Sum Queries9102 / 9791
- Subarray Sum Queries II2963 / 3045
- Distinct Values Queries8594 / 10360
- Distinct Values Queries II1608 / 1812
- Increasing Array Queries3289 / 3722
- Movie Festival Queries1886 / 2063
- Forest Queries II5300 / 5665
- Range Updates and Sums7577 / 8821
- Polynomial Queries5540 / 6416
- Range Queries and Copies3924 / 4167
- Missing Coin Sum Queries972 / 1310
Tree Algorithms
- Subordinates38416 / 40941
- Tree Matching22398 / 25693
- Tree Diameter31505 / 33195
- Tree Distances I24543 / 26180
- Tree Distances II20039 / 20898
- Company Queries I22497 / 23578
- Company Queries II21046 / 22053
- Distance Queries18958 / 20218
- Counting Paths12063 / 12699
- Subtree Queries14108 / 14964
- Path Queries11422 / 12021
- Path Queries II4817 / 6972
- Distinct Colors10902 / 11902
- Finding a Centroid8869 / 9205
- Fixed-Length Paths I4497 / 5600
- Fixed-Length Paths II2234 / 3797
Mathematics
- Josephus Queries6167 / 7648
- Exponentiation29733 / 31620
- Exponentiation II20674 / 24440
- Counting Divisors27358 / 30743
- Common Divisors17519 / 20136
- Sum of Divisors10043 / 14558
- Divisor Analysis6869 / 9023
- Prime Multiples8011 / 9233
- Counting Coprime Pairs5311 / 6082
- Next Prime2992 / 3391
- Binomial Coefficients12843 / 14140
- Creating Strings II10590 / 11135
- Distributing Apples10111 / 10831
- Christmas Party8440 / 8980
- Permutation Order1456 / 1493
- Permutation Rounds2141 / 2345
- Bracket Sequences I5627 / 6085
- Bracket Sequences II3030 / 3426
- Counting Necklaces2756 / 2968
- Counting Grids2330 / 2464
- Fibonacci Numbers8435 / 10460
- Throwing Dice4424 / 4777
- Graph Paths I4305 / 4577
- Graph Paths II3611 / 3773
- System of Linear Equations723 / 778
- Sum of Four Squares1043 / 1235
- Triangle Number Sums923 / 1090
- Dice Probability3774 / 4042
- Moving Robots1973 / 2073
- Candy Lottery2122 / 3788
- Inversion Probability656 / 2783
- Stick Game4323 / 4420
- Nim Game I5753 / 5960
- Nim Game II4561 / 4733
- Stair Game3111 / 3363
- Grundy's Game2183 / 2840
- Another Game2465 / 2641
String Algorithms
- Word Combinations7508 / 10532
- String Matching14173 / 18653
- Finding Borders10465 / 11356
- Finding Periods7519 / 8425
- Minimal Rotation3771 / 5430
- Longest Palindrome5513 / 7089
- All Palindromes1107 / 1228
- Required Substring2116 / 3115
- Palindrome Queries2583 / 2966
- Finding Patterns2508 / 3419
- Counting Patterns2359 / 2849
- Pattern Positions2006 / 2390
- Distinct Substrings2227 / 2621
- Distinct Subsequences1448 / 1525
- Repeating Substring2379 / 2711
- String Functions2089 / 2183
- Inverse Suffix Array430 / 484
- String Transform724 / 853
- Substring Order I1522 / 1671
- Substring Order II1030 / 1305
- Substring Distribution1415 / 1524
Geometry
- Point Location Test8957 / 9901
- Line Segment Intersection5335 / 6588
- Polygon Area6098 / 6414
- Point in Polygon3438 / 4289
- Polygon Lattice Points2780 / 2964
- Minimum Euclidean Distance2472 / 3417
- Convex Hull4086 / 4814
- Maximum Manhattan Distances980 / 1023
- All Manhattan Distances1022 / 1122
- Intersection Points2469 / 2656
- Line Segments Trace I527 / 545
- Line Segments Trace II439 / 459
- Lines and Queries I572 / 598
- Lines and Queries II512 / 534
- Area of Rectangles1462 / 1621
- Robot Path408 / 732
Advanced Techniques
- Meet in the Middle8690 / 11571
- Hamming Distance3801 / 4147
- Corner Subgrid Check385 / 775
- Corner Subgrid Count2558 / 2912
- Reachable Nodes2701 / 2890
- Reachability Queries1814 / 2121
- Cut and Paste1882 / 2070
- Substring Reversals1659 / 1787
- Reversals and Sums1686 / 1797
- Necessary Roads2502 / 2562
- Necessary Cities2301 / 2398
- Eulerian Subgraphs962 / 1011
- Monster Game I1464 / 1613
- Monster Game II1291 / 1374
- Subarray Squares1827 / 2106
- Houses and Schools985 / 1159
- Knuth Division1173 / 1312
- Apples and Bananas1390 / 1497
- One Bit Positions1041 / 1129
- Signal Processing1043 / 1112
- New Roads Queries2758 / 3281
- Dynamic Connectivity1260 / 1401
- Parcel Delivery1009 / 1095
- Task Assignment1164 / 1252
- Distinct Routes II764 / 856
Sliding Window Problems
- Sliding Window Sum8861 / 9146
- Sliding Window Minimum6665 / 7585
- Sliding Window Xor6542 / 6628
- Sliding Window Or2979 / 4862
- Sliding Window Distinct Values4711 / 5423
- Sliding Window Mode3633 / 3837
- Sliding Window Mex3430 / 3603
- Sliding Window Median15646 / 17753
- Sliding Window Cost10228 / 11723
- Sliding Window Inversions1893 / 1998
- Sliding Window Advertisement366 / 565
Interactive Problems
- Hidden Integer3120 / 3263
- Hidden Permutation1410 / 1620
- K-th Highest Score652 / 787
- Permuted Binary Strings759 / 778
- Colored Chairs708 / 751
- Inversion Sorting424 / 473
Bitwise Operations
- Counting Bits6634 / 8481
- Maximum Xor Subarray3907 / 4460
- Maximum Xor Subset1541 / 1695
- Number of Subset Xors1339 / 1370
- K Subset Xors702 / 815
- All Subarray Xors423 / 650
- Xor Pyramid Peak2589 / 3081
- Xor Pyramid Diagonal486 / 543
- Xor Pyramid Row413 / 481
- SOS Bit Problem2723 / 2878
- And Subset Count676 / 702
Construction Problems
- Inverse Inversions2191 / 2338
- Monotone Subsequences1335 / 1575
- Third Permutation606 / 742
- Permutation Prime Sums607 / 649
- Chess Tournament1447 / 1658
- Distinct Sums Grid229 / 333
- Filling Trominos330 / 556
- Grid Path Construction186 / 517
Advanced Graph Problems
- Nearest Shops1079 / 1367
- Prüfer Code1807 / 1930
- Tree Traversals1492 / 1628
- Course Schedule II2530 / 3513
- Acyclic Graph Edges2558 / 2706
- Strongly Connected Edges1897 / 2185
- Even Outdegree Edges1647 / 1912
- Graph Girth4154 / 4666
- Fixed Length Walk Queries536 / 588
- Transfer Speeds Sum598 / 616
- MST Edge Check980 / 1054
- MST Edge Set Check412 / 462
- MST Edge Cost575 / 597
- Network Breakdown1422 / 1538
- Tree Coin Collecting I513 / 553
- Tree Coin Collecting II300 / 339
- Tree Isomorphism I1287 / 1512
- Tree Isomorphism II1073 / 1221
- Flight Route Requests616 / 759
- Critical Cities535 / 793
- Visiting Cities809 / 1043
- Graph Coloring335 / 391
- Bus Companies383 / 393
- Split into Two Paths153 / 257
- Network Renovation1080 / 1409
- Forbidden Cities1040 / 1324
- Creating Offices501 / 650
- New Flight Routes437 / 1087
Counting Problems
- Filled Subgrid Count I873 / 970
- Filled Subgrid Count II477 / 580
- All Letter Subgrid Count I274 / 387
- All Letter Subgrid Count II176 / 256
- Border Subgrid Count I142 / 238
- Border Subgrid Count II160 / 183
- Raab Game II165 / 185
- Empty String2009 / 2428
- Permutation Inversions1173 / 1289
- Counting Bishops473 / 525
- Counting Sequences800 / 855
- Grid Paths II881 / 1109
- Counting Permutations1025 / 1150
- Grid Completion284 / 352
- Counting Reorders320 / 435
- Tournament Graph Distribution165 / 176
- Collecting Numbers Distribution168 / 176
- Functional Graph Distribution294 / 356
Additional Problems I
- Shortest Subsequence3376 / 4378
- Distinct Values Sum939 / 964
- Distinct Values Splits668 / 713
- Swap Game2327 / 2960
- Beautiful Permutation II857 / 1311
- Multiplication Table8110 / 8995
- Bubble Sort Rounds I609 / 685
- Bubble Sort Rounds II426 / 469
- Nearest Campsites I269 / 312
- Nearest Campsites II261 / 281
- Advertisement5089 / 5374
- Special Substrings1129 / 1236
- Counting LCM Arrays416 / 448
- Square Subsets318 / 351
- Subarray Sum Constraints664 / 703
- Water Containers Moves258 / 272
- Water Containers Queries292 / 306
- Stack Weights678 / 806
- Maximum Average Subarrays249 / 273
- Subsets with Fixed Average299 / 324
- Two Array Average305 / 337
- Pyramid Array921 / 1104
- Permutation Subsequence348 / 363
- Bit Inversions2665 / 2989
- Writing Numbers840 / 906
- Letter Pair Move Game252 / 342
- Maximum Building I2371 / 2474
- Sorting Methods891 / 948
- Cyclic Array1451 / 1631
- List of Sums571 / 733
Additional Problems II
- Bouncing Ball Steps355 / 389
- Bouncing Ball Cycle156 / 206
- Knight Moves Queries188 / 222
- K Subset Sums I289 / 353
- K Subset Sums II176 / 216
- Increasing Array II950 / 1082
- Food Division607 / 718
- Swap Round Sorting471 / 581
- Binary Subsequences338 / 480
- School Excursion1578 / 1670
- Coin Grid1091 / 1255
- Grid Coloring II194 / 248
- Programmers and Artists591 / 810
- Removing Digits II260 / 539
- Coin Arrangement400 / 523
- Replace with Difference197 / 230
- Grid Puzzle I640 / 699
- Grid Puzzle II629 / 685
- Bit Substrings473 / 565
- Reversal Sorting417 / 498
- Book Shop II1507 / 1713
- GCD Subsets566 / 583
- Minimum Cost Pairs201 / 247
- Same Sum Subsets177 / 330
- Mex Grid Queries959 / 1117
- Maximum Building II514 / 626
- Stick Divisions4284 / 4984
- Stick Difference125 / 365
- Coding Company1719 / 2230
- Two Stacks Sorting234 / 689