General
Introductory Problems
- Weird Algorithm99140 / 103849
- Missing Number84372 / 89008
- Repetitions73666 / 77192
- Increasing Array68759 / 71660
- Permutations60479 / 62552
- Number Spiral42811 / 46690
- Two Knights32102 / 33258
- Two Sets34696 / 37718
- Bit Strings40421 / 42698
- Trailing Zeros37839 / 40476
- Coin Piles33326 / 36785
- Palindrome Reorder30427 / 32450
- Gray Code18926 / 21652
- Tower of Hanoi17666 / 18422
- Creating Strings26238 / 27041
- Apple Division25440 / 29199
- Chessboard and Queens15117 / 15433
- Digit Queries10209 / 12281
- Grid Paths6299 / 8052
Sorting and Searching
- Distinct Numbers46471 / 50962
- Apartments33852 / 38482
- Ferris Wheel32203 / 35244
- Concert Tickets25776 / 30699
- Restaurant Customers26483 / 28912
- Movie Festival24916 / 26655
- Sum of Two Values29388 / 33544
- Maximum Subarray Sum28961 / 30468
- Stick Lengths25654 / 27106
- Missing Coin Sum17919 / 18657
- Collecting Numbers18555 / 20094
- Collecting Numbers II7394 / 9690
- Playlist19279 / 22503
- Towers19763 / 21387
- Traffic Lights15491 / 17468
- Josephus Problem I10543 / 11957
- Josephus Problem II6107 / 7963
- Nested Ranges Check5994 / 7051
- Nested Ranges Count4272 / 4932
- Room Allocation11268 / 13129
- Factory Machines14587 / 16349
- Tasks and Deadlines13125 / 13439
- Reading Books10458 / 11240
- Sum of Three Values15244 / 17295
- Sum of Four Values9662 / 10934
- Nearest Smaller Values12896 / 13409
- Subarray Sums I16638 / 17925
- Subarray Sums II15390 / 17575
- Subarray Divisibility13498 / 14901
- Subarray Distinct Values7687 / 8331
- Array Division12355 / 13120
- Sliding Window Median8173 / 9350
- Sliding Window Cost5701 / 6565
- Movie Festival II7051 / 8549
- Maximum Subarray Sum II6454 / 7751
Dynamic Programming
- Dice Combinations45849 / 48858
- Minimizing Coins39465 / 42745
- Coin Combinations I36280 / 39599
- Coin Combinations II30464 / 34982
- Removing Digits33671 / 34546
- Grid Paths32023 / 33109
- Book Shop28160 / 31511
- Array Description20333 / 22957
- Counting Towers11578 / 12294
- Edit Distance21103 / 22448
- Rectangle Cutting17602 / 19320
- Money Sums21010 / 21952
- Removal Game15002 / 16696
- Two Sets II16557 / 18090
- Increasing Subsequence17021 / 19350
- Projects11458 / 13017
- Elevator Rides6916 / 8903
- Counting Tilings3947 / 4349
- Counting Numbers5318 / 6074
Graph Algorithms
- Counting Rooms31303 / 33323
- Labyrinth20522 / 25520
- Building Roads27094 / 28262
- Message Route23013 / 24143
- Building Teams22082 / 23211
- Round Trip17144 / 18946
- Monsters10809 / 13321
- Shortest Routes I18388 / 21026
- Shortest Routes II15546 / 17056
- High Score7789 / 12807
- Flight Discount10845 / 13299
- Cycle Finding8056 / 10158
- Flight Routes7488 / 8451
- Round Trip II8994 / 10349
- Course Schedule12477 / 13037
- Longest Flight Route7701 / 10358
- Game Routes9023 / 9948
- Investigation6609 / 7189
- Planets Queries I5597 / 6842
- Planets Queries II2242 / 2788
- Planets Cycles3736 / 4211
- Road Reparation8950 / 9412
- Road Construction9440 / 9816
- Flight Routes Check8016 / 8862
- Planets and Kingdoms6459 / 6739
- Giant Pizza2598 / 2930
- Coin Collector4025 / 4568
- Mail Delivery3496 / 3894
- De Bruijn Sequence1875 / 1977
- Teleporters Path2766 / 3103
- Hamiltonian Flights3874 / 4413
- Knight's Tour1630 / 1933
- Download Speed2698 / 3828
- Police Chase2195 / 2522
- School Dance2413 / 2575
- Distinct Routes1565 / 2134
Range Queries
- Static Range Sum Queries21319 / 22318
- Static Range Minimum Queries15853 / 16980
- Dynamic Range Sum Queries16328 / 17103
- Dynamic Range Minimum Queries14843 / 15247
- Range Xor Queries15012 / 15244
- Range Update Queries11956 / 12896
- Forest Queries11728 / 12215
- Hotel Queries8568 / 9058
- List Removals7134 / 7542
- Salary Queries5281 / 6411
- Prefix Sum Queries4253 / 4655
- Pizzeria Queries3472 / 3606
- Subarray Sum Queries4419 / 4950
- Distinct Values Queries4145 / 5054
- Increasing Array Queries1495 / 1725
- Forest Queries II2851 / 3091
- Range Updates and Sums3411 / 4180
- Polynomial Queries2614 / 3076
- Range Queries and Copies1840 / 1996
Tree Algorithms
- Subordinates17631 / 19084
- Tree Matching9869 / 11657
- Tree Diameter14598 / 15652
- Tree Distances I10833 / 11764
- Tree Distances II8876 / 9280
- Company Queries I9797 / 10381
- Company Queries II9188 / 9712
- Distance Queries8575 / 9215
- Counting Paths5125 / 5498
- Subtree Queries6326 / 6781
- Path Queries5036 / 5335
- Path Queries II1787 / 2980
- Distinct Colors4800 / 5412
- Finding a Centroid3935 / 4119
- Fixed-Length Paths I1643 / 2360
- Fixed-Length Paths II668 / 1593
Mathematics
- Josephus Queries2560 / 3236
- Exponentiation14854 / 16065
- Exponentiation II10614 / 13081
- Counting Divisors12814 / 14684
- Common Divisors8590 / 10319
- Sum of Divisors4897 / 7511
- Divisor Analysis3179 / 4246
- Prime Multiples3459 / 4101
- Counting Coprime Pairs2181 / 2583
- Binomial Coefficients6003 / 6813
- Creating Strings II5043 / 5403
- Distributing Apples4928 / 5346
- Christmas Party3819 / 4155
- Bracket Sequences I2593 / 2878
- Bracket Sequences II1335 / 1541
- Counting Necklaces1292 / 1407
- Counting Grids1038 / 1111
- Fibonacci Numbers4396 / 5665
- Throwing Dice2389 / 2598
- Graph Paths I2180 / 2351
- Graph Paths II1825 / 1914
- Dice Probability2076 / 2206
- Moving Robots1044 / 1115
- Candy Lottery1601 / 1647
- Inversion Probability471 / 1438
- Stick Game2132 / 2193
- Nim Game I2690 / 2805
- Nim Game II2191 / 2291
- Stair Game1511 / 1658
- Grundy's Game970 / 1254
- Another Game1106 / 1208
String Algorithms
- Word Combinations3143 / 4826
- String Matching6281 / 9035
- Finding Borders4637 / 5195
- Finding Periods3166 / 3603
- Minimal Rotation1588 / 2596
- Longest Palindrome2396 / 3358
- Required Substring933 / 1518
- Palindrome Queries1156 / 1389
- Finding Patterns994 / 1469
- Counting Patterns895 / 1186
- Pattern Positions794 / 1015
- Distinct Substrings943 / 1138
- Repeating Substring962 / 1085
- String Functions915 / 967
- Substring Order I681 / 732
- Substring Order II447 / 567
- Substring Distribution619 / 678
Geometry
- Point Location Test4198 / 4838
- Line Segment Intersection2540 / 3321
- Polygon Area3047 / 3278
- Point in Polygon1673 / 2134
- Polygon Lattice Points1429 / 1486
- Minimum Euclidean Distance1303 / 1789
- Convex Hull2099 / 2555
Advanced Techniques
- Meet in the Middle3615 / 5576
- Hamming Distance1989 / 2156
- Beautiful Subgrids1402 / 1578
- Reachable Nodes1416 / 1540
- Reachability Queries977 / 1158
- Cut and Paste922 / 1040
- Substring Reversals808 / 888
- Reversals and Sums808 / 883
- Necessary Roads1215 / 1252
- Necessary Cities1134 / 1193
- Eulerian Subgraphs512 / 542
- Monster Game I739 / 813
- Monster Game II661 / 717
- Subarray Squares732 / 864
- Houses and Schools477 / 552
- Knuth Division560 / 635
- Apples and Bananas519 / 577
- One Bit Positions494 / 550
- Signal Processing462 / 506
- New Roads Queries1210 / 1476
- Dynamic Connectivity557 / 633
- Parcel Delivery443 / 505
- Task Assignment422 / 459
- Distinct Routes II349 / 408
Additional Problems
- Shortest Subsequence1998 / 2568
- Counting Bits2281 / 2953
- Swap Game1244 / 1603
- Prüfer Code879 / 975
- Acyclic Graph Edges1368 / 1462
- Strongly Connected Edges857 / 945
- Even Outdegree Edges784 / 913
- Multiplication Table2965 / 3386
- Advertisement2554 / 2725
- Special Substrings583 / 632
- Permutation Inversions630 / 697
- Maximum Xor Subarray1470 / 1611
- Movie Festival Queries646 / 724
- Chess Tournament732 / 838
- Tree Traversals703 / 789
- Network Renovation620 / 823
- Graph Girth1892 / 2209
- Intersection Points1160 / 1248
- Inverse Inversions635 / 666
- Monotone Subsequences432 / 481
- String Reorder512 / 566
- Stack Weights373 / 436
- Pyramid Array499 / 593
- Increasing Subsequence II1467 / 1593
- String Removals637 / 693
- Bit Inversions1492 / 1742
- Xor Pyramid781 / 996
- Writing Numbers510 / 554
- String Transform329 / 409
- Letter Pair Move Game117 / 173
- Maximum Building I1336 / 1401
- Sorting Methods536 / 574
- Cyclic Array668 / 769
- List of Sums301 / 405
- Increasing Array II506 / 576
- Food Division368 / 436
- Bit Problem971 / 1047
- Swap Round Sorting285 / 355
- Binary Subsequences149 / 237
- Tree Isomorphism I661 / 769
- Counting Sequences382 / 413
- Critical Cities252 / 400
- School Excursion867 / 926
- Coin Grid470 / 560
- Robot Path198 / 342
- Programmers and Artists317 / 407
- Course Schedule II1034 / 1466
- Removing Digits II127 / 271
- Coin Arrangement215 / 284
- Counting Bishops226 / 255
- Grid Puzzle I330 / 361
- Grid Puzzle II242 / 272
- Empty String929 / 1118
- Grid Paths507 / 631
- Bit Substrings228 / 285
- Reversal Sorting218 / 265
- Counting Reorders132 / 200
- Book Shop II656 / 747
- Network Breakdown621 / 661
- Visiting Cities460 / 600
- Missing Coin Sum Queries255 / 338
- Number Grid593 / 710
- Maximum Building II295 / 363
- Filling Trominos126 / 216
- Stick Divisions2367 / 2806
- Coding Company902 / 1148
- Flight Route Requests289 / 351
- Two Stacks Sorting94 / 325
- Tree Isomorphism II544 / 634
- Forbidden Cities455 / 596
- Area of Rectangles687 / 775
- Grid Completion132 / 175
- Creating Offices257 / 336
- Permutations II580 / 664
- Functional Graph Distribution146 / 184
- New Flight Routes204 / 489
- Grid Path Construction66 / 239