General
Introductory Problems
- Weird Algorithm100197 / 104955
- Missing Number85329 / 90014
- Repetitions74525 / 78056
- Increasing Array69601 / 72525
- Permutations61197 / 63292
- Number Spiral43331 / 47263
- Two Knights32471 / 33638
- Two Sets35119 / 38165
- Bit Strings40915 / 43222
- Trailing Zeros38281 / 40950
- Coin Piles33704 / 37210
- Palindrome Reorder30830 / 32865
- Gray Code19219 / 21970
- Tower of Hanoi17909 / 18677
- Creating Strings26564 / 27374
- Apple Division25794 / 29576
- Chessboard and Queens15318 / 15635
- Digit Queries10352 / 12456
- Grid Paths6380 / 8166
Sorting and Searching
- Distinct Numbers47088 / 51609
- Apartments34359 / 39037
- Ferris Wheel32687 / 35755
- Concert Tickets26198 / 31190
- Restaurant Customers26918 / 29378
- Movie Festival25296 / 27047
- Sum of Two Values29861 / 34065
- Maximum Subarray Sum29399 / 30932
- Stick Lengths26051 / 27510
- Missing Coin Sum18221 / 18964
- Collecting Numbers18892 / 20453
- Collecting Numbers II7522 / 9852
- Playlist19581 / 22847
- Towers20048 / 21694
- Traffic Lights15713 / 17708
- Josephus Problem I10721 / 12157
- Josephus Problem II6199 / 8105
- Nested Ranges Check6084 / 7158
- Nested Ranges Count4325 / 5004
- Room Allocation11435 / 13318
- Factory Machines14850 / 16638
- Tasks and Deadlines13288 / 13604
- Reading Books10587 / 11383
- Sum of Three Values15476 / 17557
- Sum of Four Values9799 / 11083
- Nearest Smaller Values13070 / 13590
- Subarray Sums I16919 / 18221
- Subarray Sums II15622 / 17833
- Subarray Divisibility13705 / 15116
- Subarray Distinct Values7826 / 8478
- Array Division12556 / 13336
- Sliding Window Median8318 / 9516
- Sliding Window Cost5763 / 6636
- Movie Festival II7136 / 8647
- Maximum Subarray Sum II6543 / 7851
Dynamic Programming
- Dice Combinations46440 / 49498
- Minimizing Coins39991 / 43295
- Coin Combinations I36756 / 40111
- Coin Combinations II30871 / 35436
- Removing Digits34121 / 35003
- Grid Paths32468 / 33566
- Book Shop28563 / 31945
- Array Description20627 / 23270
- Counting Towers11758 / 12485
- Edit Distance21378 / 22741
- Rectangle Cutting17827 / 19562
- Money Sums21284 / 22238
- Removal Game15191 / 16908
- Two Sets II16781 / 18339
- Increasing Subsequence17246 / 19610
- Projects11580 / 13154
- Elevator Rides7010 / 9016
- Counting Tilings4013 / 4419
- Counting Numbers5414 / 6175
Graph Algorithms
- Counting Rooms31718 / 33762
- Labyrinth20822 / 25887
- Building Roads27446 / 28618
- Message Route23322 / 24460
- Building Teams22368 / 23513
- Round Trip17374 / 19190
- Monsters10970 / 13512
- Shortest Routes I18622 / 21277
- Shortest Routes II15734 / 17264
- High Score7924 / 12982
- Flight Discount11025 / 13523
- Cycle Finding8167 / 10288
- Flight Routes7599 / 8570
- Round Trip II9135 / 10492
- Course Schedule12657 / 13231
- Longest Flight Route7845 / 10522
- Game Routes9147 / 10079
- Investigation6710 / 7302
- Planets Queries I5680 / 6932
- Planets Queries II2273 / 2823
- Planets Cycles3798 / 4277
- Road Reparation9079 / 9549
- Road Construction9576 / 9951
- Flight Routes Check8138 / 9001
- Planets and Kingdoms6569 / 6856
- Giant Pizza2689 / 3023
- Coin Collector4088 / 4636
- Mail Delivery3546 / 3949
- De Bruijn Sequence1910 / 2012
- Teleporters Path2813 / 3149
- Hamiltonian Flights3932 / 4483
- Knight's Tour1660 / 1969
- Download Speed2770 / 3900
- Police Chase2221 / 2551
- School Dance2442 / 2606
- Distinct Routes1591 / 2166
Range Queries
- Static Range Sum Queries21610 / 22619
- Static Range Minimum Queries16076 / 17217
- Dynamic Range Sum Queries16560 / 17338
- Dynamic Range Minimum Queries15072 / 15483
- Range Xor Queries15233 / 15469
- Range Update Queries12145 / 13106
- Forest Queries11884 / 12377
- Hotel Queries8696 / 9197
- List Removals7251 / 7667
- Salary Queries5362 / 6518
- Prefix Sum Queries4309 / 4720
- Pizzeria Queries3527 / 3662
- Subarray Sum Queries4482 / 5010
- Distinct Values Queries4200 / 5122
- Increasing Array Queries1515 / 1746
- Forest Queries II2879 / 3120
- Range Updates and Sums3454 / 4233
- Polynomial Queries2638 / 3113
- Range Queries and Copies1854 / 2013
Tree Algorithms
- Subordinates17891 / 19363
- Tree Matching9979 / 11797
- Tree Diameter14791 / 15845
- Tree Distances I10981 / 11927
- Tree Distances II8998 / 9407
- Company Queries I9938 / 10533
- Company Queries II9312 / 9847
- Distance Queries8695 / 9345
- Counting Paths5199 / 5580
- Subtree Queries6416 / 6872
- Path Queries5119 / 5415
- Path Queries II1830 / 3026
- Distinct Colors4886 / 5502
- Finding a Centroid3994 / 4178
- Fixed-Length Paths I1680 / 2399
- Fixed-Length Paths II692 / 1622
Mathematics
- Josephus Queries2584 / 3277
- Exponentiation15065 / 16297
- Exponentiation II10787 / 13282
- Counting Divisors13030 / 14947
- Common Divisors8738 / 10491
- Sum of Divisors4949 / 7599
- Divisor Analysis3234 / 4323
- Prime Multiples3520 / 4172
- Counting Coprime Pairs2212 / 2623
- Binomial Coefficients6074 / 6893
- Creating Strings II5094 / 5454
- Distributing Apples4977 / 5406
- Christmas Party3857 / 4194
- Bracket Sequences I2630 / 2918
- Bracket Sequences II1353 / 1565
- Counting Necklaces1307 / 1426
- Counting Grids1055 / 1129
- Fibonacci Numbers4461 / 5745
- Throwing Dice2415 / 2627
- Graph Paths I2208 / 2382
- Graph Paths II1848 / 1939
- Dice Probability2104 / 2233
- Moving Robots1058 / 1129
- Candy Lottery1625 / 1671
- Inversion Probability484 / 1453
- Stick Game2168 / 2229
- Nim Game I2733 / 2854
- Nim Game II2230 / 2331
- Stair Game1536 / 1684
- Grundy's Game991 / 1277
- Another Game1129 / 1230
String Algorithms
- Word Combinations3201 / 4902
- String Matching6465 / 9229
- Finding Borders4741 / 5302
- Finding Periods3260 / 3706
- Minimal Rotation1607 / 2630
- Longest Palindrome2441 / 3412
- Required Substring952 / 1542
- Palindrome Queries1176 / 1415
- Finding Patterns1022 / 1502
- Counting Patterns919 / 1216
- Pattern Positions810 / 1036
- Distinct Substrings975 / 1172
- Repeating Substring984 / 1108
- String Functions935 / 987
- Substring Order I697 / 748
- Substring Order II451 / 574
- Substring Distribution630 / 690
Geometry
- Point Location Test4246 / 4891
- Line Segment Intersection2580 / 3365
- Polygon Area3087 / 3318
- Point in Polygon1696 / 2166
- Polygon Lattice Points1447 / 1504
- Minimum Euclidean Distance1322 / 1809
- Convex Hull2142 / 2597
Advanced Techniques
- Meet in the Middle3671 / 5644
- Hamming Distance2013 / 2183
- Beautiful Subgrids1420 / 1597
- Reachable Nodes1437 / 1559
- Reachability Queries991 / 1177
- Cut and Paste938 / 1058
- Substring Reversals825 / 907
- Reversals and Sums822 / 900
- Necessary Roads1235 / 1272
- Necessary Cities1153 / 1212
- Eulerian Subgraphs518 / 548
- Monster Game I748 / 823
- Monster Game II670 / 726
- Subarray Squares748 / 880
- Houses and Schools484 / 560
- Knuth Division568 / 643
- Apples and Bananas531 / 587
- One Bit Positions507 / 565
- Signal Processing472 / 517
- New Roads Queries1230 / 1499
- Dynamic Connectivity562 / 645
- Parcel Delivery446 / 508
- Task Assignment431 / 470
- Distinct Routes II355 / 415
Additional Problems
- Shortest Subsequence2023 / 2597
- Counting Bits2313 / 2988
- Swap Game1273 / 1636
- Prüfer Code895 / 991
- Acyclic Graph Edges1391 / 1486
- Strongly Connected Edges877 / 965
- Even Outdegree Edges795 / 929
- Multiplication Table3036 / 3469
- Advertisement2593 / 2764
- Special Substrings600 / 650
- Permutation Inversions642 / 712
- Maximum Xor Subarray1490 / 1633
- Movie Festival Queries658 / 736
- Chess Tournament741 / 848
- Tree Traversals710 / 798
- Network Renovation627 / 830
- Graph Girth1931 / 2252
- Intersection Points1177 / 1271
- Inverse Inversions654 / 685
- Monotone Subsequences437 / 489
- String Reorder516 / 570
- Stack Weights377 / 442
- Pyramid Array503 / 603
- Increasing Subsequence II1494 / 1621
- String Removals648 / 704
- Bit Inversions1518 / 1766
- Xor Pyramid797 / 1017
- Writing Numbers512 / 556
- String Transform330 / 412
- Letter Pair Move Game120 / 177
- Maximum Building I1353 / 1419
- Sorting Methods542 / 581
- Cyclic Array677 / 778
- List of Sums303 / 407
- Increasing Array II514 / 588
- Food Division370 / 440
- Bit Problem987 / 1065
- Swap Round Sorting289 / 358
- Binary Subsequences150 / 240
- Tree Isomorphism I670 / 779
- Counting Sequences385 / 416
- Critical Cities258 / 403
- School Excursion879 / 939
- Coin Grid471 / 563
- Robot Path199 / 345
- Programmers and Artists319 / 410
- Course Schedule II1046 / 1489
- Removing Digits II128 / 278
- Coin Arrangement217 / 287
- Counting Bishops229 / 258
- Grid Puzzle I335 / 366
- Grid Puzzle II247 / 277
- Empty String941 / 1132
- Grid Paths509 / 638
- Bit Substrings238 / 298
- Reversal Sorting220 / 268
- Counting Reorders133 / 201
- Book Shop II663 / 755
- Network Breakdown628 / 668
- Visiting Cities463 / 603
- Missing Coin Sum Queries258 / 345
- Number Grid598 / 717
- Maximum Building II295 / 364
- Filling Trominos129 / 220
- Stick Divisions2397 / 2840
- Coding Company909 / 1161
- Flight Route Requests297 / 361
- Two Stacks Sorting95 / 329
- Tree Isomorphism II551 / 641
- Forbidden Cities459 / 601
- Area of Rectangles694 / 785
- Grid Completion133 / 177
- Creating Offices259 / 337
- Permutations II585 / 669
- Functional Graph Distribution148 / 185
- New Flight Routes206 / 497
- Grid Path Construction67 / 241