General
Introductory Problems
- Weird Algorithm99703 / 104447
- Missing Number84879 / 89540
- Repetitions74131 / 77659
- Increasing Array69213 / 72125
- Permutations60866 / 62948
- Number Spiral43075 / 46982
- Two Knights32307 / 33468
- Two Sets34916 / 37956
- Bit Strings40663 / 42950
- Trailing Zeros38053 / 40705
- Coin Piles33521 / 37000
- Palindrome Reorder30632 / 32662
- Gray Code19067 / 21804
- Tower of Hanoi17774 / 18541
- Creating Strings26407 / 27211
- Apple Division25629 / 29409
- Chessboard and Queens15224 / 15541
- Digit Queries10295 / 12385
- Grid Paths6345 / 8116
Sorting and Searching
- Distinct Numbers46791 / 51295
- Apartments34128 / 38784
- Ferris Wheel32469 / 35524
- Concert Tickets25992 / 30966
- Restaurant Customers26712 / 29161
- Movie Festival25115 / 26857
- Sum of Two Values29623 / 33802
- Maximum Subarray Sum29192 / 30713
- Stick Lengths25851 / 27310
- Missing Coin Sum18074 / 18816
- Collecting Numbers18724 / 20283
- Collecting Numbers II7455 / 9771
- Playlist19407 / 22646
- Towers19903 / 21541
- Traffic Lights15599 / 17584
- Josephus Problem I10632 / 12059
- Josephus Problem II6146 / 8027
- Nested Ranges Check6042 / 7108
- Nested Ranges Count4296 / 4969
- Room Allocation11356 / 13229
- Factory Machines14712 / 16487
- Tasks and Deadlines13202 / 13517
- Reading Books10524 / 11314
- Sum of Three Values15353 / 17417
- Sum of Four Values9733 / 11009
- Nearest Smaller Values12977 / 13494
- Subarray Sums I16784 / 18076
- Subarray Sums II15513 / 17713
- Subarray Divisibility13608 / 15018
- Subarray Distinct Values7763 / 8410
- Array Division12457 / 13229
- Sliding Window Median8246 / 9434
- Sliding Window Cost5738 / 6606
- Movie Festival II7094 / 8600
- Maximum Subarray Sum II6500 / 7804
Dynamic Programming
- Dice Combinations46175 / 49210
- Minimizing Coins39736 / 43033
- Coin Combinations I36524 / 39871
- Coin Combinations II30671 / 35215
- Removing Digits33907 / 34784
- Grid Paths32222 / 33317
- Book Shop28356 / 31722
- Array Description20471 / 23105
- Counting Towers11667 / 12385
- Edit Distance21240 / 22593
- Rectangle Cutting17721 / 19446
- Money Sums21149 / 22098
- Removal Game15097 / 16801
- Two Sets II16671 / 18219
- Increasing Subsequence17147 / 19489
- Projects11523 / 13089
- Elevator Rides6975 / 8970
- Counting Tilings3986 / 4391
- Counting Numbers5366 / 6124
Graph Algorithms
- Counting Rooms31501 / 33533
- Labyrinth20658 / 25688
- Building Roads27253 / 28425
- Message Route23165 / 24297
- Building Teams22239 / 23377
- Round Trip17258 / 19069
- Monsters10887 / 13412
- Shortest Routes I18517 / 21162
- Shortest Routes II15643 / 17166
- High Score7860 / 12901
- Flight Discount10930 / 13401
- Cycle Finding8113 / 10228
- Flight Routes7543 / 8509
- Round Trip II9064 / 10417
- Course Schedule12561 / 13131
- Longest Flight Route7777 / 10448
- Game Routes9077 / 10007
- Investigation6665 / 7253
- Planets Queries I5633 / 6882
- Planets Queries II2258 / 2805
- Planets Cycles3764 / 4244
- Road Reparation9007 / 9473
- Road Construction9502 / 9878
- Flight Routes Check8083 / 8939
- Planets and Kingdoms6515 / 6800
- Giant Pizza2651 / 2986
- Coin Collector4066 / 4611
- Mail Delivery3520 / 3922
- De Bruijn Sequence1893 / 1994
- Teleporters Path2791 / 3126
- Hamiltonian Flights3909 / 4452
- Knight's Tour1648 / 1954
- Download Speed2754 / 3888
- Police Chase2213 / 2542
- School Dance2431 / 2593
- Distinct Routes1585 / 2155
Range Queries
- Static Range Sum Queries21476 / 22482
- Static Range Minimum Queries15967 / 17098
- Dynamic Range Sum Queries16459 / 17237
- Dynamic Range Minimum Queries14972 / 15383
- Range Xor Queries15121 / 15356
- Range Update Queries12067 / 13018
- Forest Queries11819 / 12309
- Hotel Queries8641 / 9138
- List Removals7204 / 7615
- Salary Queries5327 / 6471
- Prefix Sum Queries4280 / 4690
- Pizzeria Queries3497 / 3628
- Subarray Sum Queries4448 / 4978
- Distinct Values Queries4171 / 5084
- Increasing Array Queries1508 / 1739
- Forest Queries II2869 / 3110
- Range Updates and Sums3436 / 4213
- Polynomial Queries2626 / 3096
- Range Queries and Copies1849 / 2007
Tree Algorithms
- Subordinates17756 / 19219
- Tree Matching9922 / 11725
- Tree Diameter14689 / 15740
- Tree Distances I10894 / 11831
- Tree Distances II8932 / 9339
- Company Queries I9852 / 10444
- Company Queries II9245 / 9773
- Distance Queries8635 / 9276
- Counting Paths5160 / 5536
- Subtree Queries6376 / 6833
- Path Queries5088 / 5386
- Path Queries II1812 / 3003
- Distinct Colors4837 / 5453
- Finding a Centroid3969 / 4153
- Fixed-Length Paths I1662 / 2381
- Fixed-Length Paths II683 / 1613
Mathematics
- Josephus Queries2574 / 3257
- Exponentiation14949 / 16170
- Exponentiation II10712 / 13189
- Counting Divisors12913 / 14801
- Common Divisors8655 / 10394
- Sum of Divisors4925 / 7552
- Divisor Analysis3208 / 4286
- Prime Multiples3485 / 4137
- Counting Coprime Pairs2192 / 2599
- Binomial Coefficients6045 / 6854
- Creating Strings II5071 / 5430
- Distributing Apples4951 / 5378
- Christmas Party3830 / 4167
- Bracket Sequences I2608 / 2894
- Bracket Sequences II1343 / 1553
- Counting Necklaces1300 / 1417
- Counting Grids1047 / 1121
- Fibonacci Numbers4425 / 5701
- Throwing Dice2400 / 2609
- Graph Paths I2189 / 2362
- Graph Paths II1835 / 1926
- Dice Probability2091 / 2220
- Moving Robots1048 / 1119
- Candy Lottery1616 / 1662
- Inversion Probability477 / 1443
- Stick Game2150 / 2211
- Nim Game I2712 / 2832
- Nim Game II2212 / 2313
- Stair Game1523 / 1671
- Grundy's Game984 / 1270
- Another Game1119 / 1221
String Algorithms
- Word Combinations3174 / 4872
- String Matching6372 / 9130
- Finding Borders4675 / 5237
- Finding Periods3206 / 3649
- Minimal Rotation1594 / 2612
- Longest Palindrome2420 / 3389
- Required Substring945 / 1532
- Palindrome Queries1168 / 1402
- Finding Patterns1009 / 1487
- Counting Patterns909 / 1203
- Pattern Positions803 / 1025
- Distinct Substrings956 / 1154
- Repeating Substring972 / 1096
- String Functions926 / 979
- Substring Order I690 / 741
- Substring Order II449 / 570
- Substring Distribution624 / 683
Geometry
- Point Location Test4223 / 4865
- Line Segment Intersection2563 / 3344
- Polygon Area3073 / 3304
- Point in Polygon1687 / 2153
- Polygon Lattice Points1440 / 1497
- Minimum Euclidean Distance1318 / 1803
- Convex Hull2129 / 2584
Advanced Techniques
- Meet in the Middle3645 / 5616
- Hamming Distance2001 / 2169
- Beautiful Subgrids1409 / 1586
- Reachable Nodes1426 / 1548
- Reachability Queries985 / 1168
- Cut and Paste935 / 1054
- Substring Reversals820 / 902
- Reversals and Sums819 / 897
- Necessary Roads1225 / 1262
- Necessary Cities1143 / 1202
- Eulerian Subgraphs515 / 545
- Monster Game I745 / 819
- Monster Game II665 / 722
- Subarray Squares736 / 868
- Houses and Schools483 / 559
- Knuth Division565 / 640
- Apples and Bananas525 / 582
- One Bit Positions501 / 558
- Signal Processing469 / 513
- New Roads Queries1220 / 1489
- Dynamic Connectivity562 / 644
- Parcel Delivery446 / 508
- Task Assignment427 / 466
- Distinct Routes II355 / 414
Additional Problems
- Shortest Subsequence2018 / 2589
- Counting Bits2299 / 2971
- Swap Game1262 / 1621
- Prüfer Code889 / 985
- Acyclic Graph Edges1384 / 1479
- Strongly Connected Edges870 / 958
- Even Outdegree Edges791 / 922
- Multiplication Table2999 / 3426
- Advertisement2581 / 2752
- Special Substrings594 / 644
- Permutation Inversions637 / 707
- Maximum Xor Subarray1482 / 1624
- Movie Festival Queries654 / 732
- Chess Tournament736 / 842
- Tree Traversals708 / 796
- Network Renovation623 / 828
- Graph Girth1916 / 2236
- Intersection Points1169 / 1258
- Inverse Inversions645 / 676
- Monotone Subsequences435 / 485
- String Reorder514 / 568
- Stack Weights374 / 438
- Pyramid Array499 / 594
- Increasing Subsequence II1485 / 1612
- String Removals644 / 700
- Bit Inversions1507 / 1755
- Xor Pyramid791 / 1008
- Writing Numbers510 / 554
- String Transform329 / 410
- Letter Pair Move Game119 / 176
- Maximum Building I1344 / 1411
- Sorting Methods538 / 577
- Cyclic Array672 / 773
- List of Sums302 / 406
- Increasing Array II511 / 583
- Food Division369 / 438
- Bit Problem980 / 1058
- Swap Round Sorting287 / 357
- Binary Subsequences150 / 238
- Tree Isomorphism I667 / 775
- Counting Sequences384 / 415
- Critical Cities257 / 403
- School Excursion874 / 933
- Coin Grid471 / 563
- Robot Path199 / 345
- Programmers and Artists317 / 407
- Course Schedule II1042 / 1477
- Removing Digits II127 / 274
- Coin Arrangement216 / 286
- Counting Bishops227 / 256
- Grid Puzzle I334 / 365
- Grid Puzzle II246 / 276
- Empty String934 / 1125
- Grid Paths508 / 632
- Bit Substrings236 / 294
- Reversal Sorting219 / 267
- Counting Reorders133 / 201
- Book Shop II661 / 753
- Network Breakdown626 / 666
- Visiting Cities461 / 601
- Missing Coin Sum Queries256 / 342
- Number Grid596 / 715
- Maximum Building II295 / 363
- Filling Trominos128 / 219
- Stick Divisions2386 / 2829
- Coding Company904 / 1152
- Flight Route Requests296 / 359
- Two Stacks Sorting95 / 328
- Tree Isomorphism II549 / 638
- Forbidden Cities455 / 597
- Area of Rectangles692 / 780
- Grid Completion132 / 176
- Creating Offices259 / 337
- Permutations II583 / 667
- Functional Graph Distribution146 / 184
- New Flight Routes205 / 496
- Grid Path Construction66 / 240