General
Introductory Problems
- Weird Algorithm177058 / 184936
- Missing Number152734 / 159637
- Repetitions132756 / 137736
- Increasing Array125146 / 129284
- Permutations109634 / 112793
- Number Spiral77917 / 84465
- Two Knights60109 / 61879
- Two Sets65346 / 69904
- Bit Strings74311 / 78201
- Trailing Zeros68801 / 72959
- Coin Piles61215 / 66582
- Palindrome Reorder56896 / 59849
- Gray Code38895 / 43366
- Tower of Hanoi36261 / 37644
- Creating Strings48013 / 49174
- Apple Division48734 / 54594
- Chessboard and Queens29672 / 30170
- Raab Game I7787 / 8719
- Mex Grid Construction7558 / 7921
- Knight Moves Grid7632 / 7799
- Grid Coloring I6415 / 6638
- Digit Queries20838 / 23865
- String Reorder5728 / 6534
- Grid Path Description11678 / 14947
Sorting and Searching
- Distinct Numbers88042 / 94717
- Apartments66201 / 72773
- Ferris Wheel63790 / 68314
- Concert Tickets51169 / 58978
- Restaurant Customers52057 / 55873
- Movie Festival50619 / 53349
- Sum of Two Values58494 / 64983
- Maximum Subarray Sum55822 / 58099
- Stick Lengths50020 / 52144
- Missing Coin Sum38309 / 39609
- Collecting Numbers39234 / 41759
- Collecting Numbers II17274 / 21476
- Playlist39154 / 44305
- Towers39118 / 41722
- Traffic Lights30474 / 33856
- Distinct Values Subarrays10564 / 11807
- Distinct Values Subsequences8138 / 8849
- Josephus Problem I23754 / 25947
- Josephus Problem II12934 / 17699
- Nested Ranges Check14176 / 16010
- Nested Ranges Count9482 / 11074
- Room Allocation23129 / 26300
- Factory Machines33527 / 36176
- Tasks and Deadlines26744 / 27260
- Reading Books21717 / 23162
- Sum of Three Values31223 / 34288
- Sum of Four Values19517 / 21524
- Nearest Smaller Values26166 / 26998
- Subarray Sums I34721 / 36794
- Subarray Sums II31689 / 37108
- Subarray Divisibility28676 / 31012
- Distinct Values Subarrays II17546 / 19063
- Array Division27159 / 28462
- Movie Festival II14775 / 17584
- Maximum Subarray Sum II13785 / 16225
Dynamic Programming
- Dice Combinations92614 / 97723
- Minimizing Coins80105 / 85733
- Coin Combinations I73189 / 78828
- Coin Combinations II62080 / 69708
- Removing Digits69052 / 70416
- Grid Paths I64812 / 66529
- Book Shop58454 / 63862
- Array Description43361 / 47775
- Counting Towers27042 / 28538
- Edit Distance43120 / 45339
- Longest Common Subsequence15168 / 15667
- Rectangle Cutting35623 / 38686
- Minimal Grid Path7088 / 11706
- Money Sums41995 / 43471
- Removal Game26117 / 33634
- Two Sets II33182 / 35475
- Mountain Range4904 / 8355
- Increasing Subsequence33676 / 37599
- Projects23724 / 26279
- Elevator Rides15594 / 19278
- Counting Tilings9134 / 9871
- Counting Numbers13662 / 15105
- Increasing Subsequence II6159 / 7218
Graph Algorithms
- Counting Rooms64411 / 67401
- Labyrinth45798 / 53781
- Building Roads56415 / 58290
- Message Route48931 / 50696
- Building Teams46165 / 48390
- Round Trip36615 / 39572
- Monsters26027 / 30041
- Shortest Routes I40420 / 44059
- Shortest Routes II32673 / 36260
- High Score21008 / 28283
- Flight Discount26911 / 30877
- Cycle Finding18982 / 22659
- Flight Routes18513 / 20422
- Round Trip II20531 / 22775
- Course Schedule27099 / 28411
- Longest Flight Route19895 / 23909
- Game Routes21670 / 22991
- Investigation16469 / 17560
- Planets Queries I14275 / 16452
- Planets Queries II5182 / 6428
- Planets Cycles8613 / 9512
- Road Reparation21106 / 21919
- Road Construction23021 / 23710
- Flight Routes Check18288 / 19654
- Planets and Kingdoms14896 / 15507
- Giant Pizza6275 / 6847
- Coin Collector9902 / 10823
- Mail Delivery7879 / 8547
- De Bruijn Sequence4150 / 4337
- Teleporters Path6117 / 6874
- Hamiltonian Flights9340 / 10556
- Knight's Tour3484 / 4167
- Download Speed6075 / 7900
- Police Chase4853 / 5383
- School Dance5326 / 5612
- Distinct Routes3760 / 4812
Range Queries
- Static Range Sum Queries45062 / 47037
- Static Range Minimum Queries30954 / 33123
- Dynamic Range Sum Queries32216 / 33581
- Dynamic Range Minimum Queries29086 / 29759
- Range Xor Queries29700 / 30089
- Range Update Queries24038 / 25658
- Forest Queries24680 / 25516
- Hotel Queries17519 / 18484
- List Removals14574 / 15259
- Salary Queries11271 / 13923
- Prefix Sum Queries9447 / 10147
- Pizzeria Queries7543 / 7797
- Visible Buildings Queries2313 / 2511
- Range Interval Queries1762 / 2341
- Subarray Sum Queries8695 / 9376
- Subarray Sum Queries II2610 / 2688
- Distinct Values Queries8255 / 9980
- Distinct Values Queries II1459 / 1655
- Increasing Array Queries3134 / 3562
- Movie Festival Queries1750 / 1922
- Forest Queries II5114 / 5469
- Range Updates and Sums7207 / 8425
- Polynomial Queries5290 / 6162
- Range Queries and Copies3725 / 3967
- Missing Coin Sum Queries883 / 1207
Tree Algorithms
- Subordinates37061 / 39534
- Tree Matching21459 / 24691
- Tree Diameter30333 / 32002
- Tree Distances I23572 / 25179
- Tree Distances II19203 / 20043
- Company Queries I21587 / 22636
- Company Queries II20196 / 21186
- Distance Queries18215 / 19440
- Counting Paths11523 / 12144
- Subtree Queries13522 / 14354
- Path Queries10910 / 11498
- Path Queries II4586 / 6696
- Distinct Colors10447 / 11414
- Finding a Centroid8505 / 8833
- Fixed-Length Paths I4257 / 5332
- Fixed-Length Paths II2093 / 3612
Mathematics
- Josephus Queries5894 / 7340
- Exponentiation28663 / 30482
- Exponentiation II20006 / 23713
- Counting Divisors26363 / 29652
- Common Divisors16943 / 19514
- Sum of Divisors9671 / 14100
- Divisor Analysis6635 / 8751
- Prime Multiples7703 / 8897
- Counting Coprime Pairs5093 / 5861
- Next Prime2730 / 3104
- Binomial Coefficients12345 / 13604
- Creating Strings II10208 / 10743
- Distributing Apples9751 / 10459
- Christmas Party8122 / 8651
- Permutation Order1307 / 1342
- Permutation Rounds1910 / 2101
- Bracket Sequences I5431 / 5885
- Bracket Sequences II2896 / 3287
- Counting Necklaces2626 / 2835
- Counting Grids2211 / 2345
- Fibonacci Numbers8060 / 10014
- Throwing Dice4258 / 4606
- Graph Paths I4131 / 4399
- Graph Paths II3463 / 3624
- System of Linear Equations660 / 715
- Sum of Four Squares944 / 1129
- Triangle Number Sums825 / 986
- Dice Probability3652 / 3919
- Moving Robots1893 / 1994
- Candy Lottery1980 / 3644
- Inversion Probability593 / 2685
- Stick Game4165 / 4262
- Nim Game I5566 / 5768
- Nim Game II4407 / 4575
- Stair Game2984 / 3230
- Grundy's Game2084 / 2726
- Another Game2361 / 2535
String Algorithms
- Word Combinations7198 / 10168
- String Matching13668 / 18005
- Finding Borders10077 / 10956
- Finding Periods7208 / 8102
- Minimal Rotation3602 / 5247
- Longest Palindrome5301 / 6862
- All Palindromes978 / 1092
- Required Substring2023 / 2991
- Palindrome Queries2473 / 2851
- Finding Patterns2350 / 3242
- Counting Patterns2232 / 2713
- Pattern Positions1884 / 2257
- Distinct Substrings2108 / 2491
- Distinct Subsequences1355 / 1432
- Repeating Substring2276 / 2605
- String Functions1995 / 2089
- Inverse Suffix Array383 / 437
- String Transform689 / 814
- Substring Order I1437 / 1585
- Substring Order II978 / 1247
- Substring Distribution1339 / 1447
Geometry
- Point Location Test8608 / 9543
- Line Segment Intersection5104 / 6334
- Polygon Area5857 / 6174
- Point in Polygon3287 / 4121
- Polygon Lattice Points2668 / 2851
- Minimum Euclidean Distance2365 / 3294
- Convex Hull3916 / 4636
- Maximum Manhattan Distances855 / 888
- All Manhattan Distances894 / 980
- Intersection Points2330 / 2508
- Line Segments Trace I468 / 483
- Line Segments Trace II390 / 409
- Lines and Queries I513 / 538
- Lines and Queries II457 / 478
- Area of Rectangles1374 / 1527
- Robot Path376 / 686
Advanced Techniques
- Meet in the Middle8325 / 11164
- Hamming Distance3670 / 4009
- Corner Subgrid Check326 / 700
- Corner Subgrid Count2500 / 2841
- Reachable Nodes2609 / 2793
- Reachability Queries1750 / 2046
- Cut and Paste1803 / 1990
- Substring Reversals1594 / 1719
- Reversals and Sums1619 / 1728
- Necessary Roads2325 / 2384
- Necessary Cities2160 / 2254
- Eulerian Subgraphs923 / 972
- Monster Game I1383 / 1530
- Monster Game II1221 / 1302
- Subarray Squares1730 / 2002
- Houses and Schools941 / 1112
- Knuth Division1127 / 1262
- Apples and Bananas1317 / 1422
- One Bit Positions994 / 1080
- Signal Processing979 / 1044
- New Roads Queries2622 / 3145
- Dynamic Connectivity1202 / 1343
- Parcel Delivery950 / 1036
- Task Assignment1096 / 1182
- Distinct Routes II724 / 815
Sliding Window Problems
- Sliding Window Sum8041 / 8301
- Sliding Window Minimum6050 / 6883
- Sliding Window Xor5912 / 5988
- Sliding Window Or2655 / 4392
- Sliding Window Distinct Values4222 / 4915
- Sliding Window Mode3288 / 3479
- Sliding Window Mex3100 / 3262
- Sliding Window Median15293 / 17373
- Sliding Window Cost9985 / 11469
- Sliding Window Inversions1660 / 1755
- Sliding Window Advertisement321 / 504
Interactive Problems
- Hidden Integer2901 / 3023
- Hidden Permutation1303 / 1507
- K-th Highest Score594 / 717
- Permuted Binary Strings695 / 714
- Colored Chairs656 / 695
- Inversion Sorting383 / 431
Bitwise Operations
- Counting Bits6238 / 8005
- Maximum Xor Subarray3687 / 4211
- Maximum Xor Subset1391 / 1527
- Number of Subset Xors1211 / 1238
- K Subset Xors633 / 742
- All Subarray Xors381 / 587
- Xor Pyramid Peak2452 / 2934
- Xor Pyramid Diagonal435 / 487
- Xor Pyramid Row375 / 439
- SOS Bit Problem2590 / 2743
- And Subset Count618 / 642
Construction Problems
- Inverse Inversions2067 / 2206
- Monotone Subsequences1251 / 1477
- Third Permutation556 / 684
- Permutation Prime Sums560 / 600
- Chess Tournament1389 / 1601
- Distinct Sums Grid198 / 296
- Filling Trominos309 / 531
- Grid Path Construction170 / 500
Advanced Graph Problems
- Nearest Shops959 / 1230
- Prüfer Code1727 / 1850
- Tree Traversals1421 / 1554
- Course Schedule II2358 / 3295
- Acyclic Graph Edges2457 / 2604
- Strongly Connected Edges1796 / 2085
- Even Outdegree Edges1581 / 1834
- Graph Girth3983 / 4489
- Fixed Length Walk Queries478 / 529
- Transfer Speeds Sum537 / 554
- MST Edge Check881 / 952
- MST Edge Set Check326 / 369
- 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 / 719
- Critical Cities504 / 754
- Visiting Cities767 / 1002
- Graph Coloring296 / 346
- Bus Companies345 / 355
- Split into Two Paths140 / 237
- Network Renovation1040 / 1363
- Forbidden Cities981 / 1266
- Creating Offices476 / 618
- New Flight Routes410 / 1040
Counting Problems
- Filled Subgrid Count I789 / 879
- Filled Subgrid Count II422 / 521
- All Letter Subgrid Count I240 / 344
- All Letter Subgrid Count II151 / 228
- Border Subgrid Count I128 / 218
- Border Subgrid Count II143 / 165
- Raab Game II145 / 165
- Empty String1923 / 2331
- Permutation Inversions1141 / 1256
- Counting Bishops445 / 498
- Counting Sequences766 / 821
- Grid Paths II851 / 1071
- Counting Permutations984 / 1109
- Grid Completion261 / 330
- Counting Reorders297 / 412
- Tournament Graph Distribution145 / 155
- Collecting Numbers Distribution153 / 160
- Functional Graph Distribution280 / 343
Additional Problems I
- Shortest Subsequence3274 / 4275
- Distinct Values Sum869 / 893
- Distinct Values Splits613 / 657
- Swap Game2260 / 2885
- Beautiful Permutation II764 / 1169
- Multiplication Table7822 / 8675
- Bubble Sort Rounds I554 / 627
- Bubble Sort Rounds II385 / 428
- Nearest Campsites I239 / 280
- Nearest Campsites II232 / 250
- Advertisement4918 / 5199
- Special Substrings1087 / 1190
- Counting LCM Arrays370 / 402
- Square Subsets286 / 315
- Subarray Sum Constraints585 / 625
- Water Containers Moves232 / 246
- Water Containers Queries265 / 279
- Stack Weights653 / 780
- Maximum Average Subarrays228 / 250
- Subsets with Fixed Average269 / 292
- Two Array Average275 / 306
- Pyramid Array863 / 1039
- Permutation Subsequence318 / 329
- Bit Inversions2570 / 2889
- Writing Numbers811 / 879
- Letter Pair Move Game235 / 325
- Maximum Building I2280 / 2380
- Sorting Methods846 / 903
- Cyclic Array1374 / 1548
- List of Sums544 / 703
Additional Problems II
- Bouncing Ball Steps317 / 349
- Bouncing Ball Cycle134 / 181
- Knight Moves Queries161 / 195
- K Subset Sums I260 / 323
- K Subset Sums II155 / 194
- Increasing Array II910 / 1038
- Food Division579 / 689
- Swap Round Sorting449 / 555
- Binary Subsequences320 / 461
- School Excursion1535 / 1621
- Coin Grid1023 / 1188
- Grid Coloring II172 / 221
- Programmers and Artists563 / 780
- Removing Digits II244 / 518
- Coin Arrangement372 / 492
- Replace with Difference173 / 207
- Grid Puzzle I606 / 664
- Grid Puzzle II590 / 645
- Bit Substrings448 / 540
- Reversal Sorting395 / 475
- Book Shop II1431 / 1630
- GCD Subsets511 / 527
- Minimum Cost Pairs181 / 227
- Same Sum Subsets157 / 299
- Mex Grid Queries930 / 1085
- Maximum Building II492 / 604
- Stick Divisions4156 / 4841
- Stick Difference105 / 336
- Coding Company1661 / 2168
- Two Stacks Sorting209 / 643