General
Introductory Problems
- Weird Algorithm96084 / 100612
- Missing Number81743 / 86248
- Repetitions71354 / 74791
- Increasing Array66579 / 69417
- Permutations58534 / 60535
- Number Spiral41461 / 45221
- Two Knights31067 / 32185
- Two Sets33510 / 36448
- Bit Strings39145 / 41352
- Trailing Zeros36665 / 39223
- Coin Piles32283 / 35629
- Palindrome Reorder29441 / 31406
- Gray Code18229 / 20827
- Tower of Hanoi17019 / 17756
- Creating Strings25358 / 26130
- Apple Division24612 / 28287
- Chessboard and Queens14616 / 14921
- Digit Queries9806 / 11819
- Grid Paths6075 / 7767
Sorting and Searching
- Distinct Numbers44868 / 49305
- Apartments32664 / 37164
- Ferris Wheel31044 / 34000
- Concert Tickets24838 / 29623
- Restaurant Customers25528 / 27879
- Movie Festival24026 / 25713
- Sum of Two Values28307 / 32347
- Maximum Subarray Sum27874 / 29348
- Stick Lengths24751 / 26159
- Missing Coin Sum17199 / 17900
- Collecting Numbers17772 / 19250
- Collecting Numbers II7099 / 9283
- Playlist18633 / 21764
- Towers19110 / 20681
- Traffic Lights14955 / 16873
- Josephus Problem I10018 / 11406
- Josephus Problem II5853 / 7604
- Nested Ranges Check5741 / 6749
- Nested Ranges Count4107 / 4742
- Room Allocation10873 / 12677
- Factory Machines13728 / 15432
- Tasks and Deadlines12636 / 12942
- Reading Books10058 / 10815
- Sum of Three Values14700 / 16665
- Sum of Four Values9289 / 10532
- Nearest Smaller Values12433 / 12932
- Subarray Sums I16015 / 17277
- Subarray Sums II14808 / 16951
- Subarray Divisibility13008 / 14365
- Subarray Distinct Values7303 / 7927
- Array Division11659 / 12387
- Sliding Window Median7818 / 8936
- Sliding Window Cost5480 / 6330
- Movie Festival II6791 / 8225
- Maximum Subarray Sum II6169 / 7385
Dynamic Programming
- Dice Combinations44097 / 47026
- Minimizing Coins37915 / 41091
- Coin Combinations I34867 / 38091
- Coin Combinations II29223 / 33617
- Removing Digits32398 / 33235
- Grid Paths30729 / 31771
- Book Shop27048 / 30291
- Array Description19507 / 22043
- Counting Towers11013 / 11692
- Edit Distance20300 / 21581
- Rectangle Cutting16970 / 18613
- Money Sums20230 / 21137
- Removal Game14426 / 16088
- Two Sets II15961 / 17410
- Increasing Subsequence16399 / 18650
- Projects11055 / 12562
- Elevator Rides6637 / 8532
- Counting Tilings3785 / 4164
- Counting Numbers5113 / 5837
Graph Algorithms
- Counting Rooms30131 / 32088
- Labyrinth19708 / 24572
- Building Roads25974 / 27078
- Message Route22105 / 23183
- Building Teams21216 / 22309
- Round Trip16460 / 18199
- Monsters10244 / 12657
- Shortest Routes I17609 / 20035
- Shortest Routes II14882 / 16308
- High Score7361 / 12258
- Flight Discount10335 / 12682
- Cycle Finding7729 / 9762
- Flight Routes7198 / 8119
- Round Trip II8651 / 9955
- Course Schedule11982 / 12498
- Longest Flight Route7347 / 9932
- Game Routes8657 / 9554
- Investigation6344 / 6902
- Planets Queries I5328 / 6528
- Planets Queries II2142 / 2673
- Planets Cycles3575 / 4031
- Road Reparation8535 / 8963
- Road Construction8997 / 9345
- Flight Routes Check7683 / 8493
- Planets and Kingdoms6203 / 6474
- Giant Pizza2478 / 2794
- Coin Collector3859 / 4383
- Mail Delivery3333 / 3718
- De Bruijn Sequence1798 / 1895
- Teleporters Path2652 / 2979
- Hamiltonian Flights3674 / 4201
- Knight's Tour1548 / 1836
- Download Speed2537 / 3645
- Police Chase2088 / 2403
- School Dance2298 / 2453
- Distinct Routes1456 / 2015
Range Queries
- Static Range Sum Queries20406 / 21361
- Static Range Minimum Queries15212 / 16299
- Dynamic Range Sum Queries15662 / 16404
- Dynamic Range Minimum Queries14246 / 14626
- Range Xor Queries14388 / 14607
- Range Update Queries11462 / 12362
- Forest Queries11258 / 11730
- Hotel Queries8187 / 8649
- List Removals6833 / 7225
- Salary Queries5029 / 6093
- Prefix Sum Queries4029 / 4419
- Pizzeria Queries3298 / 3426
- Subarray Sum Queries4206 / 4724
- Distinct Values Queries3962 / 4838
- Increasing Array Queries1429 / 1645
- Forest Queries II2737 / 2968
- Range Updates and Sums3264 / 3991
- Polynomial Queries2500 / 2939
- Range Queries and Copies1747 / 1905
Tree Algorithms
- Subordinates16933 / 18346
- Tree Matching9462 / 11180
- Tree Diameter14015 / 15038
- Tree Distances I10377 / 11281
- Tree Distances II8503 / 8885
- Company Queries I9401 / 9965
- Company Queries II8839 / 9341
- Distance Queries8269 / 8875
- Counting Paths4914 / 5271
- Subtree Queries6083 / 6516
- Path Queries4837 / 5116
- Path Queries II1647 / 2794
- Distinct Colors4619 / 5225
- Finding a Centroid3752 / 3928
- Fixed-Length Paths I1522 / 2215
- Fixed-Length Paths II631 / 1523
Mathematics
- Josephus Queries2426 / 3080
- Exponentiation14324 / 15486
- Exponentiation II10169 / 12551
- Counting Divisors12277 / 14099
- Common Divisors8278 / 9937
- Sum of Divisors4733 / 7269
- Divisor Analysis3038 / 4075
- Prime Multiples3289 / 3911
- Counting Coprime Pairs2086 / 2474
- Binomial Coefficients5741 / 6512
- Creating Strings II4826 / 5161
- Distributing Apples4723 / 5123
- Christmas Party3659 / 3986
- Bracket Sequences I2478 / 2755
- Bracket Sequences II1266 / 1460
- Counting Necklaces1230 / 1336
- Counting Grids991 / 1061
- Fibonacci Numbers4241 / 5463
- Throwing Dice2302 / 2507
- Graph Paths I2099 / 2262
- Graph Paths II1760 / 1841
- Dice Probability2015 / 2137
- Moving Robots1010 / 1078
- Candy Lottery1547 / 1590
- Inversion Probability431 / 1387
- Stick Game2059 / 2118
- Nim Game I2590 / 2696
- Nim Game II2110 / 2200
- Stair Game1463 / 1604
- Grundy's Game932 / 1202
- Another Game1054 / 1150
String Algorithms
- Word Combinations2992 / 4620
- String Matching5938 / 8624
- Finding Borders4431 / 4977
- Finding Periods3015 / 3436
- Minimal Rotation1526 / 2504
- Longest Palindrome2272 / 3198
- Required Substring893 / 1465
- Palindrome Queries1096 / 1311
- Finding Patterns941 / 1396
- Counting Patterns849 / 1133
- Pattern Positions753 / 969
- Distinct Substrings900 / 1088
- Repeating Substring905 / 1020
- String Functions881 / 928
- Substring Order I655 / 702
- Substring Order II427 / 540
- Substring Distribution582 / 636
Geometry
- Point Location Test4104 / 4574
- Line Segment Intersection2464 / 3141
- Polygon Area2869 / 3094
- Point in Polygon1571 / 2016
- Polygon Lattice Points1339 / 1390
- Minimum Euclidean Distance1231 / 1699
- Convex Hull1982 / 2407
Advanced Techniques
- Meet in the Middle3430 / 5354
- Hamming Distance1888 / 2041
- Beautiful Subgrids1334 / 1506
- Reachable Nodes1338 / 1451
- Reachability Queries927 / 1097
- Cut and Paste865 / 974
- Substring Reversals753 / 828
- Reversals and Sums754 / 824
- Necessary Roads1156 / 1188
- Necessary Cities1078 / 1132
- Eulerian Subgraphs485 / 513
- Monster Game I701 / 770
- Monster Game II623 / 676
- Subarray Squares685 / 811
- Houses and Schools450 / 517
- Knuth Division529 / 599
- Apples and Bananas499 / 550
- One Bit Positions474 / 525
- Signal Processing448 / 488
- New Roads Queries1170 / 1425
- Dynamic Connectivity527 / 598
- Parcel Delivery420 / 478
- Task Assignment394 / 427
- Distinct Routes II333 / 386
Additional Problems
- Shortest Subsequence1917 / 2469
- Counting Bits2214 / 2868
- Swap Game1197 / 1545
- Prüfer Code847 / 942
- Acyclic Graph Edges1326 / 1412
- Strongly Connected Edges817 / 898
- Even Outdegree Edges748 / 876
- Multiplication Table2690 / 3072
- Advertisement2442 / 2610
- Special Substrings556 / 602
- Permutation Inversions601 / 664
- Maximum Xor Subarray1417 / 1552
- Movie Festival Queries627 / 701
- Chess Tournament705 / 805
- Tree Traversals680 / 766
- Network Renovation593 / 790
- Graph Girth1833 / 2139
- Intersection Points1094 / 1178
- Inverse Inversions616 / 644
- Monotone Subsequences409 / 454
- String Reorder493 / 543
- Stack Weights359 / 417
- Pyramid Array487 / 578
- Increasing Subsequence II1415 / 1533
- String Removals621 / 675
- Bit Inversions1422 / 1664
- Xor Pyramid761 / 965
- Writing Numbers496 / 536
- String Transform311 / 388
- Letter Pair Move Game112 / 165
- Maximum Building I1280 / 1341
- Sorting Methods513 / 548
- Cyclic Array633 / 730
- List of Sums290 / 389
- Increasing Array II480 / 547
- Food Division353 / 419
- Bit Problem918 / 990
- Swap Round Sorting270 / 338
- Binary Subsequences143 / 224
- Tree Isomorphism I648 / 752
- Counting Sequences367 / 395
- Critical Cities240 / 380
- School Excursion825 / 879
- Coin Grid448 / 534
- Robot Path193 / 329
- Programmers and Artists305 / 389
- Course Schedule II987 / 1411
- Removing Digits II122 / 255
- Coin Arrangement206 / 271
- Counting Bishops214 / 239
- Grid Puzzle I313 / 342
- Grid Puzzle II225 / 252
- Empty String895 / 1078
- Grid Paths493 / 611
- Bit Substrings217 / 270
- Reversal Sorting208 / 250
- Counting Reorders127 / 193
- Book Shop II630 / 717
- Network Breakdown599 / 635
- Visiting Cities439 / 569
- Missing Coin Sum Queries245 / 320
- Number Grid577 / 690
- Maximum Building II286 / 350
- Filling Trominos121 / 202
- Stick Divisions2277 / 2696
- Coding Company862 / 1099
- Flight Route Requests275 / 333
- Two Stacks Sorting87 / 312
- Tree Isomorphism II543 / 616
- Forbidden Cities441 / 572
- Area of Rectangles655 / 738
- Grid Completion127 / 167
- Creating Offices246 / 320
- Permutations II556 / 634
- Functional Graph Distribution142 / 175
- New Flight Routes199 / 475
- Grid Path Construction62 / 226