General
Introductory Problems
- Weird Algorithm180823 / 188837
- Missing Number155985 / 162983
- Repetitions135406 / 140463
- Increasing Array127669 / 131863
- Permutations111686 / 114901
- Number Spiral79432 / 86099
- Two Knights61334 / 63124
- Two Sets66641 / 71271
- Bit Strings75704 / 79650
- Trailing Zeros70105 / 74330
- Coin Piles62434 / 67864
- Palindrome Reorder57979 / 60966
- Gray Code39701 / 44236
- Tower of Hanoi37017 / 38419
- Creating Strings48831 / 50002
- Apple Division49664 / 55588
- Chessboard and Queens30252 / 30756
- Raab Game I8250 / 9206
- Mex Grid Construction7970 / 8353
- Knight Moves Grid8043 / 8224
- Grid Coloring I6779 / 7012
- Digit Queries21238 / 24280
- String Reorder6017 / 6858
- Grid Path Description11918 / 15218
Sorting and Searching
- Distinct Numbers89956 / 96752
- Apartments67556 / 74222
- Ferris Wheel65173 / 69767
- Concert Tickets52313 / 60206
- Restaurant Customers53101 / 56957
- Movie Festival51655 / 54414
- Sum of Two Values59765 / 66328
- Maximum Subarray Sum56862 / 59164
- Stick Lengths50909 / 53068
- Missing Coin Sum39090 / 40416
- Collecting Numbers39996 / 42557
- Collecting Numbers II17689 / 21935
- Playlist39928 / 45126
- Towers39869 / 42513
- Traffic Lights31022 / 34442
- Distinct Values Subarrays11141 / 12404
- Distinct Values Subsequences8586 / 9317
- Josephus Problem I24277 / 26487
- Josephus Problem II13179 / 18052
- Nested Ranges Check14515 / 16370
- Nested Ranges Count9711 / 11326
- Room Allocation23645 / 26846
- Factory Machines34320 / 36997
- Tasks and Deadlines27312 / 27831
- Reading Books22225 / 23673
- Sum of Three Values31902 / 35015
- Sum of Four Values19879 / 21904
- Nearest Smaller Values26744 / 27589
- Subarray Sums I35507 / 37606
- Subarray Sums II32409 / 37890
- Subarray Divisibility29235 / 31606
- Distinct Values Subarrays II17906 / 19432
- Array Division27704 / 29022
- Movie Festival II15121 / 17954
- Maximum Subarray Sum II14106 / 16578
Dynamic Programming
- Dice Combinations94336 / 99505
- Minimizing Coins81633 / 87313
- Coin Combinations I74595 / 80320
- Coin Combinations II63353 / 71100
- Removing Digits70332 / 71705
- Grid Paths I66074 / 67816
- Book Shop59674 / 65175
- Array Description44237 / 48683
- Counting Towers27703 / 29207
- Edit Distance43998 / 46267
- Longest Common Subsequence15980 / 16492
- Rectangle Cutting36255 / 39367
- Minimal Grid Path7550 / 12322
- Money Sums42824 / 44323
- Removal Game26749 / 34291
- Two Sets II33818 / 36115
- Mountain Range5251 / 8830
- Increasing Subsequence34344 / 38417
- Projects24277 / 26922
- Elevator Rides15989 / 19707
- Counting Tilings9379 / 10121
- Counting Numbers14040 / 15497
- Increasing Subsequence II6462 / 7566
Graph Algorithms
- Counting Rooms65789 / 68830
- Labyrinth46832 / 54848
- Building Roads57595 / 59500
- Message Route49978 / 51756
- Building Teams47164 / 49425
- Round Trip37438 / 40428
- Monsters26713 / 30755
- Shortest Routes I41427 / 45115
- Shortest Routes II33369 / 37015
- High Score21573 / 28900
- Flight Discount27570 / 31588
- Cycle Finding19495 / 23197
- Flight Routes18987 / 20901
- Round Trip II21075 / 23367
- Course Schedule27755 / 29108
- Longest Flight Route20400 / 24428
- Game Routes22196 / 23517
- Investigation16943 / 18046
- Planets Queries I14714 / 16910
- Planets Queries II5351 / 6628
- Planets Cycles8863 / 9771
- Road Reparation21703 / 22527
- Road Construction23644 / 24340
- Flight Routes Check18767 / 20142
- Planets and Kingdoms15375 / 15986
- Giant Pizza6469 / 7054
- Coin Collector10248 / 11183
- Mail Delivery8107 / 8785
- De Bruijn Sequence4275 / 4465
- Teleporters Path6271 / 7032
- Hamiltonian Flights9619 / 10851
- Knight's Tour3595 / 4286
- Download Speed6232 / 8073
- Police Chase4974 / 5507
- School Dance5473 / 5760
- Distinct Routes3865 / 4927
Range Queries
- Static Range Sum Queries46151 / 48163
- Static Range Minimum Queries31662 / 33870
- Dynamic Range Sum Queries33006 / 34391
- Dynamic Range Minimum Queries29792 / 30471
- Range Xor Queries30342 / 30737
- Range Update Queries24631 / 26266
- Forest Queries25234 / 26082
- Hotel Queries18005 / 18980
- List Removals14988 / 15685
- Salary Queries11639 / 14310
- Prefix Sum Queries9749 / 10453
- Pizzeria Queries7783 / 8041
- Visible Buildings Queries2482 / 2687
- Range Interval Queries1882 / 2498
- Subarray Sum Queries8949 / 9637
- Subarray Sum Queries II2844 / 2922
- Distinct Values Queries8462 / 10218
- Distinct Values Queries II1555 / 1754
- Increasing Array Queries3233 / 3665
- Movie Festival Queries1821 / 1995
- Forest Queries II5225 / 5587
- Range Updates and Sums7439 / 8671
- Polynomial Queries5448 / 6320
- Range Queries and Copies3838 / 4081
- Missing Coin Sum Queries933 / 1269
Tree Algorithms
- Subordinates37837 / 40335
- Tree Matching22037 / 25304
- Tree Diameter31024 / 32711
- Tree Distances I24164 / 25782
- Tree Distances II19728 / 20582
- Company Queries I22151 / 23212
- Company Queries II20717 / 21718
- Distance Queries18664 / 19914
- Counting Paths11865 / 12492
- Subtree Queries13859 / 14701
- Path Queries11203 / 11795
- Path Queries II4722 / 6852
- Distinct Colors10723 / 11713
- Finding a Centroid8704 / 9039
- Fixed-Length Paths I4382 / 5472
- Fixed-Length Paths II2173 / 3712
Mathematics
- Josephus Queries6055 / 7520
- Exponentiation29291 / 31151
- Exponentiation II20420 / 24157
- Counting Divisors26904 / 30240
- Common Divisors17289 / 19874
- Sum of Divisors9881 / 14372
- Divisor Analysis6773 / 8918
- Prime Multiples7899 / 9104
- Counting Coprime Pairs5235 / 6005
- Next Prime2883 / 3267
- Binomial Coefficients12628 / 13907
- Creating Strings II10451 / 10995
- Distributing Apples9965 / 10677
- Christmas Party8334 / 8865
- Permutation Order1396 / 1431
- Permutation Rounds2057 / 2253
- Bracket Sequences I5555 / 6013
- Bracket Sequences II2981 / 3377
- Counting Necklaces2713 / 2924
- Counting Grids2289 / 2423
- Fibonacci Numbers8315 / 10318
- Throwing Dice4357 / 4710
- Graph Paths I4238 / 4510
- Graph Paths II3558 / 3721
- System of Linear Equations701 / 754
- Sum of Four Squares1006 / 1196
- Triangle Number Sums888 / 1056
- Dice Probability3726 / 3994
- Moving Robots1940 / 2040
- Candy Lottery2070 / 3736
- Inversion Probability630 / 2742
- Stick Game4261 / 4358
- Nim Game I5683 / 5888
- Nim Game II4503 / 4674
- Stair Game3063 / 3312
- Grundy's Game2145 / 2803
- Another Game2427 / 2602
String Algorithms
- Word Combinations7395 / 10403
- String Matching13967 / 18406
- Finding Borders10309 / 11192
- Finding Periods7394 / 8294
- Minimal Rotation3704 / 5354
- Longest Palindrome5420 / 6991
- All Palindromes1055 / 1172
- Required Substring2074 / 3060
- Palindrome Queries2541 / 2922
- Finding Patterns2445 / 3346
- Counting Patterns2315 / 2798
- Pattern Positions1960 / 2339
- Distinct Substrings2172 / 2561
- Distinct Subsequences1408 / 1485
- Repeating Substring2332 / 2663
- String Functions2042 / 2134
- Inverse Suffix Array403 / 457
- String Transform709 / 836
- Substring Order I1484 / 1633
- Substring Order II1010 / 1283
- Substring Distribution1378 / 1486
Geometry
- Point Location Test8789 / 9730
- Line Segment Intersection5225 / 6467
- Polygon Area5977 / 6292
- Point in Polygon3369 / 4213
- Polygon Lattice Points2723 / 2908
- Minimum Euclidean Distance2414 / 3351
- Convex Hull4012 / 4733
- Maximum Manhattan Distances919 / 956
- All Manhattan Distances965 / 1061
- Intersection Points2409 / 2595
- Line Segments Trace I492 / 508
- Line Segments Trace II411 / 430
- Lines and Queries I535 / 560
- Lines and Queries II481 / 502
- Area of Rectangles1423 / 1578
- Robot Path395 / 708
Advanced Techniques
- Meet in the Middle8552 / 11425
- Hamming Distance3749 / 4088
- Corner Subgrid Check364 / 742
- Corner Subgrid Count2533 / 2884
- Reachable Nodes2658 / 2845
- Reachability Queries1789 / 2093
- Cut and Paste1835 / 2022
- Substring Reversals1621 / 1746
- Reversals and Sums1651 / 1761
- Necessary Roads2416 / 2475
- Necessary Cities2239 / 2333
- Eulerian Subgraphs943 / 992
- Monster Game I1426 / 1575
- Monster Game II1253 / 1336
- Subarray Squares1788 / 2066
- Houses and Schools967 / 1139
- Knuth Division1151 / 1290
- Apples and Bananas1357 / 1463
- One Bit Positions1022 / 1110
- Signal Processing1018 / 1087
- New Roads Queries2695 / 3220
- Dynamic Connectivity1234 / 1375
- Parcel Delivery979 / 1065
- Task Assignment1129 / 1215
- Distinct Routes II747 / 839
Sliding Window Problems
- Sliding Window Sum8464 / 8736
- Sliding Window Minimum6378 / 7244
- Sliding Window Xor6246 / 6326
- Sliding Window Or2827 / 4650
- Sliding Window Distinct Values4480 / 5178
- Sliding Window Mode3463 / 3661
- Sliding Window Mex3272 / 3440
- Sliding Window Median15476 / 17566
- Sliding Window Cost10106 / 11599
- Sliding Window Inversions1757 / 1856
- Sliding Window Advertisement340 / 528
Interactive Problems
- Hidden Integer3024 / 3159
- Hidden Permutation1362 / 1570
- K-th Highest Score623 / 751
- Permuted Binary Strings726 / 745
- Colored Chairs683 / 725
- Inversion Sorting403 / 451
Bitwise Operations
- Counting Bits6479 / 8298
- Maximum Xor Subarray3822 / 4365
- Maximum Xor Subset1479 / 1625
- Number of Subset Xors1287 / 1317
- K Subset Xors671 / 783
- All Subarray Xors408 / 629
- Xor Pyramid Peak2532 / 3024
- Xor Pyramid Diagonal464 / 519
- Xor Pyramid Row397 / 463
- SOS Bit Problem2667 / 2821
- And Subset Count657 / 682
Construction Problems
- Inverse Inversions2141 / 2286
- Monotone Subsequences1294 / 1529
- Third Permutation583 / 714
- Permutation Prime Sums585 / 627
- Chess Tournament1419 / 1629
- Distinct Sums Grid211 / 313
- Filling Trominos318 / 543
- Grid Path Construction177 / 506
Advanced Graph Problems
- Nearest Shops1034 / 1317
- Prüfer Code1777 / 1900
- Tree Traversals1457 / 1592
- Course Schedule II2438 / 3409
- Acyclic Graph Edges2518 / 2665
- Strongly Connected Edges1854 / 2141
- Even Outdegree Edges1618 / 1878
- Graph Girth4082 / 4594
- Fixed Length Walk Queries507 / 559
- Transfer Speeds Sum573 / 592
- MST Edge Check941 / 1014
- MST Edge Set Check396 / 443
- MST Edge Cost553 / 575
- Network Breakdown1382 / 1497
- Tree Coin Collecting I488 / 527
- Tree Coin Collecting II283 / 322
- Tree Isomorphism I1260 / 1481
- Tree Isomorphism II1041 / 1188
- Flight Route Requests598 / 738
- Critical Cities521 / 776
- Visiting Cities791 / 1026
- Graph Coloring313 / 364
- Bus Companies364 / 374
- Split into Two Paths145 / 245
- Network Renovation1062 / 1389
- Forbidden Cities1011 / 1295
- Creating Offices491 / 634
- New Flight Routes420 / 1065
Counting Problems
- Filled Subgrid Count I844 / 939
- Filled Subgrid Count II458 / 560
- All Letter Subgrid Count I261 / 369
- All Letter Subgrid Count II165 / 242
- Border Subgrid Count I134 / 226
- Border Subgrid Count II149 / 171
- Raab Game II153 / 173
- Empty String1972 / 2383
- Permutation Inversions1156 / 1273
- Counting Bishops463 / 515
- Counting Sequences787 / 842
- Grid Paths II869 / 1094
- Counting Permutations1004 / 1129
- Grid Completion274 / 341
- Counting Reorders310 / 425
- Tournament Graph Distribution155 / 165
- Collecting Numbers Distribution160 / 168
- Functional Graph Distribution287 / 349
Additional Problems I
- Shortest Subsequence3333 / 4333
- Distinct Values Sum903 / 927
- Distinct Values Splits641 / 686
- Swap Game2299 / 2928
- Beautiful Permutation II813 / 1238
- Multiplication Table7968 / 8837
- Bubble Sort Rounds I588 / 662
- Bubble Sort Rounds II407 / 451
- Nearest Campsites I254 / 297
- Nearest Campsites II247 / 265
- Advertisement5007 / 5288
- Special Substrings1110 / 1215
- Counting LCM Arrays398 / 430
- Square Subsets307 / 339
- Subarray Sum Constraints633 / 672
- Water Containers Moves245 / 259
- Water Containers Queries281 / 295
- Stack Weights666 / 793
- Maximum Average Subarrays238 / 262
- Subsets with Fixed Average286 / 310
- Two Array Average287 / 318
- Pyramid Array897 / 1081
- Permutation Subsequence331 / 344
- Bit Inversions2627 / 2947
- Writing Numbers828 / 894
- Letter Pair Move Game241 / 332
- Maximum Building I2337 / 2438
- Sorting Methods864 / 921
- Cyclic Array1414 / 1592
- List of Sums557 / 717
Additional Problems II
- Bouncing Ball Steps340 / 373
- Bouncing Ball Cycle142 / 192
- Knight Moves Queries176 / 210
- K Subset Sums I276 / 340
- K Subset Sums II165 / 203
- Increasing Array II937 / 1069
- Food Division591 / 701
- Swap Round Sorting461 / 571
- Binary Subsequences330 / 471
- School Excursion1558 / 1647
- Coin Grid1060 / 1224
- Grid Coloring II182 / 235
- Programmers and Artists577 / 795
- Removing Digits II251 / 526
- Coin Arrangement388 / 509
- Replace with Difference188 / 221
- Grid Puzzle I626 / 684
- Grid Puzzle II609 / 664
- Bit Substrings460 / 552
- Reversal Sorting404 / 485
- Book Shop II1468 / 1670
- GCD Subsets545 / 561
- Minimum Cost Pairs191 / 236
- Same Sum Subsets168 / 315
- Mex Grid Queries948 / 1105
- Maximum Building II501 / 613
- Stick Divisions4229 / 4925
- Stick Difference114 / 352
- Coding Company1696 / 2207
- Two Stacks Sorting220 / 658