General
Introductory Problems
- Weird Algorithm130623 / 136839
- Missing Number112338 / 118093
- Repetitions97926 / 102176
- Increasing Array91890 / 95454
- Permutations80638 / 83251
- Number Spiral57054 / 62334
- Two Knights43271 / 44724
- Two Sets46935 / 50780
- Bit Strings54131 / 57219
- Trailing Zeros50578 / 53958
- Coin Piles44706 / 49155
- Palindrome Reorder41376 / 43800
- Gray Code27013 / 30617
- Tower of Hanoi25061 / 26099
- Creating Strings35224 / 36211
- Apple Division34922 / 39702
- Chessboard and Queens20877 / 21290
- Raab Game I423 / 481
- Mex Grid Construction438 / 464
- Knight Moves Grid423 / 429
- Grid Coloring I303 / 313
- Digit Queries14873 / 17597
- String Reorder790 / 897
- Grid Paths8413 / 10980
Sorting and Searching
- Distinct Numbers63383 / 68807
- Apartments46508 / 52087
- Ferris Wheel44507 / 48261
- Concert Tickets35886 / 42192
- Restaurant Customers36677 / 39769
- Movie Festival34759 / 36965
- Sum of Two Values40953 / 46279
- Maximum Subarray Sum39903 / 41783
- Stick Lengths35571 / 37365
- Missing Coin Sum26139 / 27156
- Collecting Numbers26808 / 28897
- Collecting Numbers II10799 / 14073
- Playlist26985 / 31170
- Towers27567 / 29677
- Traffic Lights21275 / 23993
- Distinct Values Subarrays597 / 631
- Distinct Values Subsequences408 / 445
- Josephus Problem I15933 / 17762
- Josephus Problem II8678 / 11892
- Nested Ranges Check8944 / 10434
- Nested Ranges Count6171 / 7296
- Room Allocation15829 / 18348
- Factory Machines22332 / 24594
- Tasks and Deadlines18342 / 18758
- Reading Books14732 / 15822
- Sum of Three Values21735 / 24301
- Sum of Four Values13499 / 15178
- Nearest Smaller Values18083 / 18739
- Subarray Sums I23656 / 25424
- Subarray Sums II21150 / 25558
- Subarray Divisibility19671 / 21618
- Distinct Values Subarrays II11330 / 12749
- Array Division18605 / 19660
- Movie Festival II9791 / 11993
- Maximum Subarray Sum II8987 / 10828
Dynamic Programming
- Dice Combinations64497 / 68506
- Minimizing Coins55583 / 59954
- Coin Combinations I50763 / 55210
- Coin Combinations II42733 / 48784
- Removing Digits47472 / 48536
- Grid Paths44922 / 46327
- Book Shop39761 / 44110
- Array Description28936 / 32464
- Counting Towers17205 / 18268
- Edit Distance29502 / 31277
- Longest Common Subsequence598 / 624
- Rectangle Cutting24504 / 26857
- Minimal Grid Path260 / 400
- Money Sums29416 / 30635
- Removal Game16151 / 23450
- Two Sets II23096 / 25079
- Mountain Range243 / 375
- Increasing Subsequence23754 / 26843
- Projects16125 / 18206
- Elevator Rides10034 / 12818
- Counting Tilings5809 / 6393
- Counting Numbers7830 / 8972
- Increasing Subsequence II2122 / 2285
Graph Algorithms
- Counting Rooms44144 / 46638
- Labyrinth29797 / 36487
- Building Roads38385 / 39890
- Message Route32637 / 34096
- Building Teams30810 / 32753
- Round Trip24281 / 26703
- Monsters15971 / 19325
- Shortest Routes I26403 / 29595
- Shortest Routes II21329 / 24265
- High Score12137 / 18312
- Flight Discount16345 / 19548
- Cycle Finding11543 / 14570
- Flight Routes11142 / 12514
- Round Trip II13016 / 14827
- Course Schedule17363 / 18550
- Longest Flight Route11593 / 14947
- Game Routes13286 / 14422
- Investigation9782 / 10595
- Planets Queries I8509 / 10129
- Planets Queries II3096 / 3919
- Planets Cycles5314 / 5984
- Road Reparation13176 / 13781
- Road Construction14393 / 14916
- Flight Routes Check11782 / 12882
- Planets and Kingdoms9360 / 9727
- Giant Pizza3866 / 4298
- Coin Collector5976 / 6722
- Mail Delivery5097 / 5624
- De Bruijn Sequence2687 / 2820
- Teleporters Path3819 / 4473
- Hamiltonian Flights5788 / 6615
- Knight's Tour2176 / 2677
- Download Speed4071 / 5399
- Police Chase3133 / 3546
- School Dance3461 / 3688
- Distinct Routes2325 / 3110
Range Queries
- Static Range Sum Queries30505 / 31885
- Static Range Minimum Queries21709 / 23291
- Dynamic Range Sum Queries22489 / 23504
- Dynamic Range Minimum Queries20543 / 21052
- Range Xor Queries21239 / 21545
- Range Update Queries16687 / 17990
- Forest Queries16808 / 17455
- Hotel Queries11933 / 12770
- List Removals9957 / 10549
- Salary Queries7202 / 9299
- Prefix Sum Queries6206 / 6782
- Pizzeria Queries4993 / 5207
- Visible Buildings Queries184 / 188
- Range Interval Queries136 / 162
- Subarray Sum Queries6269 / 6865
- Subarray Sum Queries II157 / 165
- Distinct Values Queries5573 / 7064
- Distinct Values Queries II113 / 127
- Increasing Array Queries2171 / 2508
- Movie Festival Queries857 / 963
- Forest Queries II3807 / 4120
- Range Updates and Sums4909 / 5932
- Polynomial Queries3648 / 4309
- Range Queries and Copies2585 / 2791
- Missing Coin Sum Queries346 / 480
Tree Algorithms
- Subordinates25177 / 27044
- Tree Matching14029 / 16502
- Tree Diameter20567 / 21914
- Tree Distances I15370 / 16623
- Tree Distances II12636 / 13194
- Company Queries I13959 / 14755
- Company Queries II13083 / 13766
- Distance Queries11969 / 12895
- Counting Paths7317 / 7823
- Subtree Queries9031 / 9663
- Path Queries7211 / 7653
- Path Queries II2821 / 4367
- Distinct Colors6888 / 7676
- Finding a Centroid5630 / 5871
- Fixed-Length Paths I2606 / 3466
- Fixed-Length Paths II1171 / 2308
Mathematics
- Josephus Queries3829 / 4811
- Exponentiation20428 / 21918
- Exponentiation II14585 / 17669
- Counting Divisors18498 / 21020
- Common Divisors12199 / 14328
- Sum of Divisors6822 / 10294
- Divisor Analysis4539 / 6117
- Prime Multiples5104 / 6052
- Counting Coprime Pairs3305 / 3907
- Next Prime228 / 240
- Binomial Coefficients8456 / 9478
- Creating Strings II7208 / 7664
- Distributing Apples6970 / 7536
- Christmas Party5410 / 5856
- Permutation Order93 / 95
- Permutation Rounds111 / 116
- Bracket Sequences I3787 / 4163
- Bracket Sequences II1959 / 2265
- Counting Necklaces1795 / 1964
- Counting Grids1448 / 1560
- Fibonacci Numbers5996 / 7607
- Throwing Dice3123 / 3409
- Graph Paths I2936 / 3159
- Graph Paths II2447 / 2565
- System of Linear Equations55 / 58
- Sum of Four Squares90 / 105
- Triangle Number Sums62 / 85
- Dice Probability2685 / 2900
- Moving Robots1368 / 1457
- Candy Lottery1190 / 2444
- Inversion Probability283 / 1927
- Stick Game2991 / 3063
- Nim Game I3970 / 4129
- Nim Game II3174 / 3315
- Stair Game2132 / 2331
- Grundy's Game1426 / 1874
- Another Game1633 / 1771
String Algorithms
- Word Combinations4751 / 7064
- String Matching9459 / 12956
- Finding Borders6897 / 7603
- Finding Periods4882 / 5564
- Minimal Rotation2345 / 3708
- Longest Palindrome3613 / 4858
- All Palindromes67 / 70
- Required Substring1342 / 2133
- Palindrome Queries1726 / 2030
- Finding Patterns1533 / 2226
- Counting Patterns1451 / 1829
- Pattern Positions1226 / 1526
- Distinct Substrings1417 / 1703
- Distinct Subsequences828 / 891
- Repeating Substring1585 / 1781
- String Functions1368 / 1437
- Inverse Suffix Array31 / 35
- String Transform408 / 510
- Substring Order I972 / 1106
- Substring Order II643 / 830
- Substring Distribution903 / 987
Geometry
- Point Location Test6070 / 6832
- Line Segment Intersection3614 / 4627
- Polygon Area4258 / 4537
- Point in Polygon2275 / 2962
- Polygon Lattice Points1966 / 2042
- Minimum Euclidean Distance1703 / 2432
- Convex Hull2871 / 3459
- Maximum Manhattan Distances63 / 65
- All Manhattan Distances76 / 81
- Intersection Points1578 / 1706
- Line Segments Trace I37 / 38
- Line Segments Trace II28 / 29
- Lines and Queries I43 / 46
- Lines and Queries II34 / 37
- Area of Rectangles915 / 1031
- Robot Path245 / 437
Advanced Techniques
- Meet in the Middle5521 / 7959
- Hamming Distance2795 / 3042
- Corner Subgrid Check55 / 71
- Corner Subgrid Count1989 / 2225
- Reachable Nodes1966 / 2129
- Reachability Queries1324 / 1574
- Cut and Paste1288 / 1443
- Substring Reversals1127 / 1238
- Reversals and Sums1134 / 1232
- Necessary Roads1652 / 1695
- Necessary Cities1538 / 1616
- Eulerian Subgraphs684 / 724
- Monster Game I996 / 1106
- Monster Game II878 / 952
- Subarray Squares1118 / 1348
- Houses and Schools631 / 758
- Knuth Division749 / 858
- Apples and Bananas797 / 878
- One Bit Positions675 / 750
- Signal Processing628 / 683
- New Roads Queries1790 / 2189
- Dynamic Connectivity823 / 935
- Parcel Delivery610 / 690
- Task Assignment696 / 745
- Distinct Routes II473 / 549
Sliding Window Problems
- Sliding Window Sum440 / 452
- Sliding Window Minimum301 / 360
- Sliding Window Xor373 / 384
- Sliding Window Or140 / 280
- Sliding Window Distinct Values294 / 298
- Sliding Window Mode224 / 228
- Sliding Window Mex207 / 211
- Sliding Window Median12057 / 13807
- Sliding Window Cost8063 / 9317
- Sliding Window Inversions149 / 159
- Sliding Window Advertisement24 / 31
Interactive Problems
- Hidden Integer281 / 291
- Hidden Permutation126 / 155
- K-th Highest Score43 / 49
- Permuted Binary Strings71 / 72
- Colored Chairs65 / 67
- Inversion Sorting41 / 44
Bitwise Operations
- Counting Bits3101 / 3937
- Maximum Xor Subarray1981 / 2179
- Maximum Xor Subset92 / 99
- Number of Subset Xors87 / 88
- K Subset Xors45 / 48
- All Subarray Xors40 / 48
- Xor Pyramid Peak1430 / 1797
- Xor Pyramid Diagonal43 / 48
- Xor Pyramid Row34 / 36
- SOS Bit Problem1489 / 1598
- And Subset Count39 / 39
Construction Problems
- Inverse Inversions927 / 980
- Monotone Subsequences597 / 688
- Third Permutation44 / 47
- Permutation Prime Sums48 / 51
- Chess Tournament934 / 1084
- Distinct Sums Grid12 / 17
- Filling Trominos191 / 317
- Grid Path Construction97 / 384
Advanced Graph Problems
- Nearest Shops64 / 74
- Prüfer Code1202 / 1314
- Tree Traversals916 / 1024
- Course Schedule II1409 / 2008
- Acyclic Graph Edges1825 / 1940
- Strongly Connected Edges1218 / 1357
- Even Outdegree Edges1102 / 1294
- Graph Girth2687 / 3101
- Fixed Length Walk Queries40 / 41
- Transfer Speeds Sum52 / 52
- MST Edge Check44 / 46
- MST Edge Set Check23 / 23
- MST Edge Cost33 / 34
- Network Breakdown781 / 830
- Tree Coin Collecting I35 / 37
- Tree Coin Collecting II14 / 15
- Tree Isomorphism I924 / 1068
- Tree Isomorphism II728 / 838
- Flight Route Requests377 / 458
- Critical Cities336 / 516
- Visiting Cities565 / 747
- Graph Coloring25 / 28
- Bus Companies28 / 29
- Split into Two Paths14 / 18
- Network Renovation811 / 1075
- Forbidden Cities651 / 861
- Creating Offices344 / 447
- New Flight Routes269 / 671
Counting Problems
- Filled Subgrid Count I46 / 48
- Filled Subgrid Count II18 / 22
- All Letter Subgrid Count I11 / 19
- All Letter Subgrid Count II10 / 10
- Border Subgrid Count I7 / 19
- Border Subgrid Count II9 / 12
- Raab Game II9 / 10
- Empty String1294 / 1572
- Permutation Inversions856 / 941
- Counting Bishops301 / 341
- Counting Sequences517 / 559
- Grid Paths625 / 782
- Counting Permutations742 / 844
- Grid Completion168 / 221
- Counting Reorders170 / 259
- Tournament Graph Distribution11 / 11
- Collecting Numbers Distribution15 / 15
- Functional Graph Distribution192 / 241
Additional Problems I
- Shortest Subsequence2582 / 3441
- Distinct Values Sum68 / 73
- Distinct Values Splits51 / 52
- Swap Game1750 / 2231
- Beautiful Permutation II25 / 32
- Multiplication Table5276 / 5926
- Bubble Sort Rounds I24 / 28
- Bubble Sort Rounds II14 / 14
- Nearest Campsites I16 / 20
- Nearest Campsites II14 / 18
- Advertisement3605 / 3826
- Special Substrings838 / 920
- Counting LCM Arrays26 / 26
- Square Subsets26 / 26
- Subarray Sum Constraints20 / 21
- Water Containers Moves14 / 15
- Water Containers Queries18 / 19
- Stack Weights493 / 581
- Maximum Average Subarrays15 / 17
- Subsets with Fixed Average21 / 21
- Two Array Average23 / 24
- Pyramid Array615 / 745
- Permutation Subsequence24 / 25
- Bit Inversions1993 / 2290
- Writing Numbers642 / 698
- Letter Pair Move Game163 / 238
- Maximum Building I1789 / 1873
- Sorting Methods684 / 734
- Cyclic Array952 / 1087
- List of Sums389 / 519
Additional Problems II
- Bouncing Ball Steps20 / 20
- Bouncing Ball Cycle12 / 17
- Knight Moves Queries21 / 24
- K Subset Sums I21 / 23
- K Subset Sums II12 / 14
- Increasing Array II679 / 784
- Food Division456 / 542
- Swap Round Sorting359 / 444
- Binary Subsequences239 / 359
- School Excursion1145 / 1220
- Coin Grid686 / 819
- Grid Coloring II20 / 25
- Programmers and Artists429 / 561
- Removing Digits II174 / 391
- Coin Arrangement276 / 366
- Replace with Difference18 / 21
- Grid Puzzle I434 / 479
- Grid Puzzle II367 / 410
- Bit Substrings303 / 378
- Reversal Sorting294 / 361
- Book Shop II940 / 1092
- GCD Subsets55 / 58
- Minimum Cost Pairs16 / 19
- Same Sum Subsets18 / 26
- Mex Grid Queries709 / 847
- Maximum Building II362 / 450
- Stick Divisions3271 / 3866
- Stick Difference4 / 19
- Coding Company1209 / 1603
- Two Stacks Sorting138 / 423