General
Introductory Problems
- Weird Algorithm179672 / 187639
- Missing Number155047 / 162011
- Repetitions134624 / 139648
- Increasing Array126942 / 131121
- Permutations111102 / 114298
- Number Spiral78993 / 85616
- Two Knights60998 / 62781
- Two Sets66291 / 70898
- Bit Strings75317 / 79256
- Trailing Zeros69723 / 73923
- Coin Piles62100 / 67512
- Palindrome Reorder57684 / 60667
- Gray Code39495 / 44000
- Tower of Hanoi36805 / 38207
- Creating Strings48617 / 49784
- Apple Division49417 / 55321
- Chessboard and Queens30102 / 30604
- Raab Game I8116 / 9068
- Mex Grid Construction7856 / 8239
- Knight Moves Grid7921 / 8099
- Grid Coloring I6677 / 6910
- Digit Queries21125 / 24165
- String Reorder5942 / 6775
- Grid Path Description11862 / 15156
Sorting and Searching
- Distinct Numbers89458 / 96205
- Apartments67215 / 73854
- Ferris Wheel64827 / 69393
- Concert Tickets52055 / 59940
- Restaurant Customers52842 / 56685
- Movie Festival51391 / 54143
- Sum of Two Values59443 / 65970
- Maximum Subarray Sum56609 / 58906
- Stick Lengths50693 / 52840
- Missing Coin Sum38912 / 40228
- Collecting Numbers39809 / 42359
- Collecting Numbers II17592 / 21828
- Playlist39757 / 44938
- Towers39680 / 42307
- Traffic Lights30909 / 34317
- Distinct Values Subarrays11013 / 12273
- Distinct Values Subsequences8481 / 9206
- Josephus Problem I24156 / 26366
- Josephus Problem II13131 / 17985
- Nested Ranges Check14428 / 16276
- Nested Ranges Count9661 / 11270
- Room Allocation23508 / 26698
- Factory Machines34099 / 36768
- Tasks and Deadlines27160 / 27677
- Reading Books22086 / 23535
- Sum of Three Values31736 / 34831
- Sum of Four Values19793 / 21817
- Nearest Smaller Values26607 / 27452
- Subarray Sums I35314 / 37409
- Subarray Sums II32221 / 37690
- Subarray Divisibility29080 / 31443
- Distinct Values Subarrays II17814 / 19338
- Array Division27556 / 28868
- Movie Festival II15043 / 17875
- Maximum Subarray Sum II14027 / 16488
Dynamic Programming
- Dice Combinations93895 / 99035
- Minimizing Coins81265 / 86930
- Coin Combinations I74250 / 79961
- Coin Combinations II63048 / 70784
- Removing Digits70026 / 71398
- Grid Paths I65788 / 67525
- Book Shop59389 / 64869
- Array Description44054 / 48484
- Counting Towers27547 / 29044
- Edit Distance43796 / 46062
- Longest Common Subsequence15785 / 16298
- Rectangle Cutting36098 / 39187
- Minimal Grid Path7433 / 12177
- Money Sums42610 / 44103
- Removal Game26593 / 34119
- Two Sets II33668 / 35964
- Mountain Range5163 / 8710
- Increasing Subsequence34175 / 38230
- Projects24153 / 26787
- Elevator Rides15895 / 19605
- Counting Tilings9324 / 10061
- Counting Numbers13945 / 15405
- Increasing Subsequence II6387 / 7481
Graph Algorithms
- Counting Rooms65420 / 68455
- Labyrinth46559 / 54567
- Building Roads57284 / 59185
- Message Route49710 / 51485
- Building Teams46897 / 49152
- Round Trip37197 / 40188
- Monsters26544 / 30579
- Shortest Routes I41202 / 44879
- Shortest Routes II33210 / 36829
- High Score21425 / 28738
- Flight Discount27416 / 31416
- Cycle Finding19383 / 23082
- Flight Routes18883 / 20797
- Round Trip II20915 / 23195
- Course Schedule27598 / 28950
- Longest Flight Route20265 / 24285
- Game Routes22052 / 23375
- Investigation16825 / 17924
- Planets Queries I14614 / 16803
- Planets Queries II5299 / 6571
- Planets Cycles8789 / 9694
- Road Reparation21543 / 22361
- Road Construction23494 / 24187
- Flight Routes Check18631 / 20004
- Planets and Kingdoms15230 / 15842
- Giant Pizza6425 / 7005
- Coin Collector10148 / 11081
- Mail Delivery8048 / 8725
- De Bruijn Sequence4240 / 4432
- Teleporters Path6240 / 6998
- Hamiltonian Flights9550 / 10781
- Knight's Tour3571 / 4261
- Download Speed6180 / 8016
- Police Chase4942 / 5472
- School Dance5436 / 5723
- Distinct Routes3837 / 4899
Range Queries
- Static Range Sum Queries45873 / 47880
- Static Range Minimum Queries31493 / 33690
- Dynamic Range Sum Queries32784 / 34163
- Dynamic Range Minimum Queries29586 / 30263
- Range Xor Queries30169 / 30560
- Range Update Queries24479 / 26107
- Forest Queries25084 / 25927
- Hotel Queries17871 / 18844
- List Removals14880 / 15573
- Salary Queries11549 / 14217
- Prefix Sum Queries9662 / 10368
- Pizzeria Queries7719 / 7977
- Visible Buildings Queries2427 / 2628
- Range Interval Queries1846 / 2453
- Subarray Sum Queries8868 / 9555
- Subarray Sum Queries II2752 / 2828
- Distinct Values Queries8414 / 10164
- Distinct Values Queries II1528 / 1725
- Increasing Array Queries3212 / 3644
- Movie Festival Queries1806 / 1978
- Forest Queries II5201 / 5558
- Range Updates and Sums7386 / 8617
- Polynomial Queries5415 / 6288
- Range Queries and Copies3807 / 4050
- Missing Coin Sum Queries920 / 1257
Tree Algorithms
- Subordinates37647 / 40142
- Tree Matching21896 / 25150
- Tree Diameter30873 / 32557
- Tree Distances I24009 / 25623
- Tree Distances II19598 / 20451
- Company Queries I22030 / 23092
- Company Queries II20602 / 21604
- Distance Queries18555 / 19796
- Counting Paths11788 / 12416
- Subtree Queries13777 / 14617
- Path Queries11126 / 11718
- Path Queries II4687 / 6814
- Distinct Colors10656 / 11642
- Finding a Centroid8653 / 8985
- Fixed-Length Paths I4351 / 5440
- Fixed-Length Paths II2142 / 3680
Mathematics
- Josephus Queries6018 / 7480
- Exponentiation29077 / 30919
- Exponentiation II20283 / 24007
- Counting Divisors26757 / 30075
- Common Divisors17197 / 19784
- Sum of Divisors9825 / 14294
- Divisor Analysis6732 / 8866
- Prime Multiples7843 / 9047
- Counting Coprime Pairs5200 / 5967
- Next Prime2854 / 3235
- Binomial Coefficients12556 / 13828
- Creating Strings II10394 / 10933
- Distributing Apples9922 / 10630
- Christmas Party8286 / 8815
- Permutation Order1373 / 1408
- Permutation Rounds2020 / 2215
- Bracket Sequences I5527 / 5984
- Bracket Sequences II2963 / 3359
- Counting Necklaces2692 / 2902
- Counting Grids2270 / 2404
- Fibonacci Numbers8267 / 10261
- Throwing Dice4331 / 4683
- Graph Paths I4211 / 4481
- Graph Paths II3530 / 3693
- System of Linear Equations694 / 747
- Sum of Four Squares994 / 1182
- Triangle Number Sums876 / 1043
- Dice Probability3710 / 3978
- Moving Robots1930 / 2030
- Candy Lottery2057 / 3719
- Inversion Probability622 / 2730
- Stick Game4241 / 4338
- Nim Game I5658 / 5863
- Nim Game II4478 / 4649
- Stair Game3042 / 3290
- Grundy's Game2130 / 2784
- Another Game2406 / 2580
String Algorithms
- Word Combinations7330 / 10320
- String Matching13871 / 18287
- Finding Borders10235 / 11114
- Finding Periods7337 / 8238
- Minimal Rotation3669 / 5315
- Longest Palindrome5377 / 6945
- All Palindromes1037 / 1153
- Required Substring2058 / 3037
- Palindrome Queries2524 / 2903
- Finding Patterns2416 / 3313
- Counting Patterns2291 / 2771
- Pattern Positions1938 / 2314
- Distinct Substrings2154 / 2542
- Distinct Subsequences1394 / 1471
- Repeating Substring2313 / 2644
- String Functions2023 / 2115
- Inverse Suffix Array396 / 450
- String Transform700 / 826
- Substring Order I1470 / 1618
- Substring Order II1001 / 1272
- Substring Distribution1366 / 1474
Geometry
- Point Location Test8750 / 9687
- Line Segment Intersection5189 / 6428
- Polygon Area5944 / 6258
- Point in Polygon3342 / 4185
- Polygon Lattice Points2708 / 2892
- Minimum Euclidean Distance2400 / 3334
- Convex Hull3982 / 4703
- Maximum Manhattan Distances906 / 941
- All Manhattan Distances950 / 1043
- Intersection Points2394 / 2578
- Line Segments Trace I488 / 504
- Line Segments Trace II409 / 428
- Lines and Queries I532 / 557
- Lines and Queries II478 / 499
- Area of Rectangles1405 / 1559
- Robot Path392 / 704
Advanced Techniques
- Meet in the Middle8498 / 11363
- Hamming Distance3731 / 4069
- Corner Subgrid Check355 / 732
- Corner Subgrid Count2526 / 2874
- Reachable Nodes2646 / 2831
- Reachability Queries1783 / 2085
- Cut and Paste1827 / 2014
- Substring Reversals1615 / 1740
- Reversals and Sums1643 / 1753
- Necessary Roads2372 / 2432
- Necessary Cities2205 / 2299
- Eulerian Subgraphs936 / 985
- Monster Game I1418 / 1567
- Monster Game II1245 / 1328
- Subarray Squares1776 / 2051
- Houses and Schools962 / 1134
- Knuth Division1144 / 1283
- Apples and Bananas1348 / 1455
- One Bit Positions1015 / 1103
- Signal Processing1007 / 1076
- New Roads Queries2685 / 3209
- Dynamic Connectivity1227 / 1368
- Parcel Delivery972 / 1058
- Task Assignment1119 / 1205
- Distinct Routes II743 / 834
Sliding Window Problems
- Sliding Window Sum8354 / 8622
- Sliding Window Minimum6296 / 7148
- Sliding Window Xor6163 / 6241
- Sliding Window Or2776 / 4580
- Sliding Window Distinct Values4417 / 5113
- Sliding Window Mode3418 / 3614
- Sliding Window Mex3230 / 3396
- Sliding Window Median15432 / 17518
- Sliding Window Cost10075 / 11565
- Sliding Window Inversions1740 / 1838
- Sliding Window Advertisement335 / 521
Interactive Problems
- Hidden Integer2995 / 3127
- Hidden Permutation1354 / 1562
- K-th Highest Score616 / 742
- Permuted Binary Strings723 / 742
- Colored Chairs677 / 719
- Inversion Sorting399 / 448
Bitwise Operations
- Counting Bits6418 / 8225
- Maximum Xor Subarray3784 / 4320
- Maximum Xor Subset1451 / 1596
- Number of Subset Xors1264 / 1293
- K Subset Xors659 / 771
- All Subarray Xors400 / 618
- Xor Pyramid Peak2512 / 3003
- Xor Pyramid Diagonal457 / 512
- Xor Pyramid Row393 / 459
- SOS Bit Problem2649 / 2803
- And Subset Count651 / 675
Construction Problems
- Inverse Inversions2124 / 2267
- Monotone Subsequences1279 / 1514
- Third Permutation573 / 704
- Permutation Prime Sums575 / 617
- Chess Tournament1412 / 1623
- Distinct Sums Grid207 / 307
- Filling Trominos315 / 539
- Grid Path Construction175 / 505
Advanced Graph Problems
- Nearest Shops1016 / 1299
- Prüfer Code1766 / 1889
- Tree Traversals1450 / 1585
- Course Schedule II2417 / 3376
- Acyclic Graph Edges2503 / 2650
- Strongly Connected Edges1842 / 2131
- Even Outdegree Edges1604 / 1865
- Graph Girth4056 / 4567
- Fixed Length Walk Queries497 / 549
- Transfer Speeds Sum562 / 580
- MST Edge Check921 / 993
- MST Edge Set Check391 / 438
- MST Edge Cost545 / 567
- Network Breakdown1370 / 1484
- Tree Coin Collecting I476 / 514
- Tree Coin Collecting II276 / 314
- Tree Isomorphism I1253 / 1475
- Tree Isomorphism II1037 / 1183
- Flight Route Requests593 / 734
- Critical Cities516 / 770
- Visiting Cities784 / 1019
- Graph Coloring312 / 363
- Bus Companies361 / 371
- Split into Two Paths143 / 244
- Network Renovation1056 / 1383
- Forbidden Cities1005 / 1288
- Creating Offices490 / 632
- New Flight Routes419 / 1057
Counting Problems
- Filled Subgrid Count I836 / 928
- Filled Subgrid Count II451 / 551
- All Letter Subgrid Count I258 / 365
- All Letter Subgrid Count II164 / 242
- Border Subgrid Count I134 / 226
- Border Subgrid Count II147 / 170
- Raab Game II152 / 172
- Empty String1960 / 2371
- Permutation Inversions1153 / 1270
- Counting Bishops460 / 511
- Counting Sequences782 / 837
- Grid Paths II865 / 1090
- Counting Permutations1002 / 1126
- Grid Completion271 / 338
- Counting Reorders309 / 424
- Tournament Graph Distribution153 / 164
- Collecting Numbers Distribution159 / 167
- Functional Graph Distribution286 / 348
Additional Problems I
- Shortest Subsequence3322 / 4322
- Distinct Values Sum899 / 923
- Distinct Values Splits638 / 681
- Swap Game2290 / 2919
- Beautiful Permutation II802 / 1222
- Multiplication Table7930 / 8798
- Bubble Sort Rounds I583 / 657
- Bubble Sort Rounds II403 / 448
- Nearest Campsites I252 / 295
- Nearest Campsites II246 / 264
- Advertisement4987 / 5268
- Special Substrings1108 / 1212
- Counting LCM Arrays393 / 425
- Square Subsets304 / 334
- Subarray Sum Constraints620 / 658
- Water Containers Moves243 / 257
- Water Containers Queries278 / 292
- Stack Weights663 / 791
- Maximum Average Subarrays236 / 259
- Subsets with Fixed Average283 / 308
- Two Array Average284 / 315
- Pyramid Array888 / 1070
- Permutation Subsequence328 / 340
- Bit Inversions2619 / 2938
- Writing Numbers825 / 891
- Letter Pair Move Game241 / 331
- Maximum Building I2308 / 2409
- Sorting Methods860 / 917
- Cyclic Array1409 / 1585
- List of Sums553 / 713
Additional Problems II
- Bouncing Ball Steps335 / 368
- Bouncing Ball Cycle139 / 189
- Knight Moves Queries173 / 207
- K Subset Sums I272 / 336
- K Subset Sums II162 / 201
- Increasing Array II931 / 1062
- Food Division588 / 698
- Swap Round Sorting459 / 568
- Binary Subsequences328 / 469
- School Excursion1552 / 1641
- Coin Grid1052 / 1216
- Grid Coloring II181 / 232
- Programmers and Artists574 / 793
- Removing Digits II250 / 525
- Coin Arrangement381 / 502
- Replace with Difference183 / 216
- Grid Puzzle I621 / 679
- Grid Puzzle II604 / 659
- Bit Substrings458 / 550
- Reversal Sorting401 / 481
- Book Shop II1460 / 1663
- GCD Subsets540 / 556
- Minimum Cost Pairs188 / 234
- Same Sum Subsets164 / 314
- Mex Grid Queries942 / 1097
- Maximum Building II497 / 609
- Stick Divisions4214 / 4905
- Stick Difference112 / 351
- Coding Company1689 / 2200
- Two Stacks Sorting213 / 650