General
Introductory Problems
- Weird Algorithm177062 / 184940
- Missing Number152736 / 159639
- Repetitions132759 / 137739
- Increasing Array125146 / 129284
- Permutations109637 / 112796
- Number Spiral77920 / 84469
- Two Knights60112 / 61881
- Two Sets65348 / 69907
- Bit Strings74313 / 78203
- Trailing Zeros68803 / 72962
- Coin Piles61216 / 66583
- Palindrome Reorder56896 / 59849
- Gray Code38895 / 43366
- Tower of Hanoi36262 / 37644
- Creating Strings48014 / 49175
- Apple Division48735 / 54596
- Chessboard and Queens29672 / 30170
- Raab Game I7787 / 8719
- Mex Grid Construction7558 / 7922
- Knight Moves Grid7632 / 7799
- Grid Coloring I6415 / 6638
- Digit Queries20840 / 23867
- String Reorder5729 / 6535
- Grid Path Description11678 / 14948
Sorting and Searching
- Distinct Numbers88045 / 94720
- Apartments66201 / 72773
- Ferris Wheel63790 / 68315
- Concert Tickets51169 / 58978
- Restaurant Customers52057 / 55873
- Movie Festival50621 / 53351
- Sum of Two Values58497 / 64985
- Maximum Subarray Sum55823 / 58100
- Stick Lengths50020 / 52144
- Missing Coin Sum38312 / 39611
- Collecting Numbers39236 / 41761
- Collecting Numbers II17274 / 21476
- Playlist39156 / 44306
- Towers39120 / 41724
- Traffic Lights30474 / 33856
- Distinct Values Subarrays10564 / 11807
- Distinct Values Subsequences8139 / 8851
- Josephus Problem I23756 / 25948
- Josephus Problem II12934 / 17699
- Nested Ranges Check14176 / 16010
- Nested Ranges Count9482 / 11074
- Room Allocation23130 / 26301
- Factory Machines33527 / 36176
- Tasks and Deadlines26744 / 27260
- Reading Books21718 / 23163
- Sum of Three Values31225 / 34290
- Sum of Four Values19518 / 21526
- Nearest Smaller Values26166 / 26998
- Subarray Sums I34723 / 36794
- Subarray Sums II31690 / 37109
- Subarray Divisibility28676 / 31012
- Distinct Values Subarrays II17546 / 19063
- Array Division27159 / 28462
- Movie Festival II14775 / 17585
- Maximum Subarray Sum II13785 / 16225
Dynamic Programming
- Dice Combinations92615 / 97724
- Minimizing Coins80106 / 85734
- Coin Combinations I73191 / 78829
- Coin Combinations II62080 / 69709
- Removing Digits69053 / 70416
- Grid Paths I64813 / 66530
- Book Shop58458 / 63866
- Array Description43363 / 47777
- Counting Towers27043 / 28539
- Edit Distance43121 / 45341
- Longest Common Subsequence15169 / 15668
- Rectangle Cutting35625 / 38688
- Minimal Grid Path7089 / 11707
- Money Sums41996 / 43472
- Removal Game26117 / 33634
- Two Sets II33183 / 35475
- Mountain Range4905 / 8356
- Increasing Subsequence33676 / 37599
- Projects23724 / 26279
- Elevator Rides15595 / 19279
- Counting Tilings9135 / 9872
- Counting Numbers13662 / 15105
- Increasing Subsequence II6159 / 7218
Graph Algorithms
- Counting Rooms64412 / 67402
- Labyrinth45801 / 53783
- Building Roads56416 / 58291
- Message Route48932 / 50697
- Building Teams46166 / 48391
- Round Trip36615 / 39572
- Monsters26028 / 30043
- Shortest Routes I40421 / 44060
- Shortest Routes II32673 / 36260
- High Score21009 / 28283
- Flight Discount26911 / 30877
- Cycle Finding18983 / 22660
- Flight Routes18513 / 20422
- Round Trip II20531 / 22775
- Course Schedule27102 / 28414
- Longest Flight Route19895 / 23909
- Game Routes21671 / 22992
- Investigation16469 / 17560
- Planets Queries I14275 / 16452
- Planets Queries II5182 / 6428
- Planets Cycles8613 / 9512
- Road Reparation21107 / 21920
- Road Construction23023 / 23712
- Flight Routes Check18289 / 19655
- Planets and Kingdoms14896 / 15507
- Giant Pizza6275 / 6847
- Coin Collector9902 / 10823
- Mail Delivery7879 / 8547
- De Bruijn Sequence4150 / 4337
- Teleporters Path6119 / 6875
- Hamiltonian Flights9340 / 10558
- Knight's Tour3484 / 4167
- Download Speed6076 / 7901
- 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 Queries29087 / 29760
- Range Xor Queries29700 / 30089
- Range Update Queries24039 / 25659
- Forest Queries24681 / 25517
- Hotel Queries17519 / 18484
- List Removals14574 / 15259
- Salary Queries11271 / 13923
- Prefix Sum Queries9447 / 10147
- Pizzeria Queries7544 / 7798
- Visible Buildings Queries2313 / 2511
- Range Interval Queries1763 / 2342
- 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
- Subordinates37062 / 39535
- Tree Matching21460 / 24692
- Tree Diameter30334 / 32003
- Tree Distances I23573 / 25180
- Tree Distances II19203 / 20043
- Company Queries I21587 / 22637
- Company Queries II20196 / 21186
- Distance Queries18216 / 19441
- 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 Queries5895 / 7341
- Exponentiation28665 / 30484
- Exponentiation II20006 / 23713
- Counting Divisors26363 / 29652
- Common Divisors16944 / 19515
- Sum of Divisors9672 / 14101
- Divisor Analysis6635 / 8751
- Prime Multiples7704 / 8898
- Counting Coprime Pairs5093 / 5861
- Next Prime2730 / 3104
- Binomial Coefficients12346 / 13605
- Creating Strings II10208 / 10743
- Distributing Apples9752 / 10460
- Christmas Party8123 / 8652
- 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 Borders10078 / 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 Subsequences1356 / 1433
- 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 Middle8326 / 11165
- Hamming Distance3671 / 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 / 6884
- Sliding Window Xor5912 / 5988
- Sliding Window Or2656 / 4392
- Sliding Window Distinct Values4223 / 4917
- Sliding Window Mode3288 / 3479
- Sliding Window Mex3101 / 3263
- Sliding Window Median15293 / 17373
- Sliding Window Cost9985 / 11469
- Sliding Window Inversions1661 / 1756
- 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 Table7823 / 8676
- 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