General
Introductory Problems
- Weird Algorithm99152 / 103859
- Missing Number84379 / 89018
- Repetitions73669 / 77196
- Increasing Array68764 / 71665
- Permutations60485 / 62558
- Number Spiral42814 / 46694
- Two Knights32105 / 33260
- Two Sets34697 / 37720
- Bit Strings40421 / 42699
- Trailing Zeros37840 / 40478
- Coin Piles33328 / 36788
- Palindrome Reorder30430 / 32453
- Gray Code18927 / 21653
- Tower of Hanoi17666 / 18422
- Creating Strings26239 / 27043
- Apple Division25441 / 29201
- Chessboard and Queens15118 / 15435
- Digit Queries10211 / 12283
- Grid Paths6299 / 8052
Sorting and Searching
- Distinct Numbers46474 / 50965
- Apartments33855 / 38484
- Ferris Wheel32206 / 35247
- Concert Tickets25778 / 30703
- Restaurant Customers26486 / 28914
- Movie Festival24917 / 26657
- Sum of Two Values29390 / 33545
- Maximum Subarray Sum28961 / 30468
- Stick Lengths25656 / 27107
- Missing Coin Sum17921 / 18658
- Collecting Numbers18558 / 20097
- Collecting Numbers II7394 / 9690
- Playlist19280 / 22505
- Towers19764 / 21388
- Traffic Lights15491 / 17468
- Josephus Problem I10543 / 11957
- Josephus Problem II6107 / 7963
- Nested Ranges Check5994 / 7051
- Nested Ranges Count4272 / 4932
- Room Allocation11268 / 13129
- Factory Machines14588 / 16350
- Tasks and Deadlines13125 / 13439
- Reading Books10458 / 11240
- Sum of Three Values15244 / 17295
- Sum of Four Values9662 / 10934
- Nearest Smaller Values12897 / 13410
- Subarray Sums I16638 / 17925
- Subarray Sums II15390 / 17575
- Subarray Divisibility13498 / 14901
- Subarray Distinct Values7688 / 8332
- Array Division12356 / 13121
- Sliding Window Median8173 / 9350
- Sliding Window Cost5701 / 6565
- Movie Festival II7052 / 8550
- Maximum Subarray Sum II6454 / 7751
Dynamic Programming
- Dice Combinations45852 / 48860
- Minimizing Coins39465 / 42747
- Coin Combinations I36281 / 39600
- Coin Combinations II30464 / 34982
- Removing Digits33674 / 34549
- Grid Paths32024 / 33110
- Book Shop28162 / 31512
- Array Description20334 / 22958
- Counting Towers11578 / 12295
- Edit Distance21103 / 22448
- Rectangle Cutting17602 / 19320
- Money Sums21011 / 21953
- Removal Game15003 / 16697
- Two Sets II16557 / 18090
- Increasing Subsequence17022 / 19354
- Projects11459 / 13018
- Elevator Rides6916 / 8903
- Counting Tilings3947 / 4349
- Counting Numbers5318 / 6074
Graph Algorithms
- Counting Rooms31306 / 33328
- Labyrinth20523 / 25521
- Building Roads27096 / 28264
- Message Route23014 / 24144
- Building Teams22083 / 23212
- Round Trip17144 / 18946
- Monsters10809 / 13322
- Shortest Routes I18389 / 21027
- Shortest Routes II15547 / 17056
- High Score7789 / 12807
- Flight Discount10845 / 13299
- Cycle Finding8056 / 10158
- Flight Routes7489 / 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 / 9413
- Road Construction9441 / 9817
- Flight Routes Check8016 / 8862
- Planets and Kingdoms6459 / 6739
- Giant Pizza2598 / 2930
- Coin Collector4025 / 4568
- Mail Delivery3496 / 3894
- De Bruijn Sequence1876 / 1977
- Teleporters Path2767 / 3104
- Hamiltonian Flights3874 / 4413
- Knight's Tour1630 / 1933
- Download Speed2698 / 3828
- Police Chase2195 / 2522
- School Dance2413 / 2575
- Distinct Routes1565 / 2134
Range Queries
- Static Range Sum Queries21321 / 22320
- Static Range Minimum Queries15854 / 16981
- Dynamic Range Sum Queries16331 / 17106
- Dynamic Range Minimum Queries14845 / 15249
- Range Xor Queries15013 / 15244
- Range Update Queries11957 / 12897
- Forest Queries11729 / 12216
- Hotel Queries8570 / 9060
- List Removals7135 / 7543
- Salary Queries5282 / 6413
- Prefix Sum Queries4253 / 4655
- Pizzeria Queries3472 / 3606
- Subarray Sum Queries4419 / 4951
- 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 Diameter14599 / 15653
- Tree Distances I10834 / 11766
- Tree Distances II8876 / 9280
- Company Queries I9798 / 10382
- Company Queries II9189 / 9713
- Distance Queries8576 / 9217
- Counting Paths5125 / 5499
- Subtree Queries6326 / 6781
- Path Queries5036 / 5335
- Path Queries II1787 / 2980
- Distinct Colors4801 / 5413
- Finding a Centroid3935 / 4119
- Fixed-Length Paths I1643 / 2360
- Fixed-Length Paths II668 / 1593
Mathematics
- Josephus Queries2560 / 3236
- Exponentiation14854 / 16065
- Exponentiation II10614 / 13081
- Counting Divisors12816 / 14686
- Common Divisors8590 / 10320
- Sum of Divisors4897 / 7511
- Divisor Analysis3180 / 4247
- Prime Multiples3459 / 4102
- Counting Coprime Pairs2181 / 2583
- Binomial Coefficients6003 / 6813
- Creating Strings II5044 / 5404
- Distributing Apples4929 / 5347
- Christmas Party3819 / 4155
- Bracket Sequences I2594 / 2879
- 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 Lottery1602 / 1648
- 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 Matching6282 / 9036
- Finding Borders4638 / 5196
- 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 Area3048 / 3279
- Point in Polygon1673 / 2134
- Polygon Lattice Points1429 / 1486
- Minimum Euclidean Distance1303 / 1789
- Convex Hull2099 / 2555
Advanced Techniques
- Meet in the Middle3616 / 5577
- 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 Table2966 / 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 Divisions2368 / 2808
- 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 / 490
- Grid Path Construction66 / 239