General
Introductory Problems
- Weird Algorithm98877 / 103572
- Missing Number84137 / 88758
- Repetitions73468 / 76979
- Increasing Array68576 / 71465
- Permutations60301 / 62373
- Number Spiral42686 / 46559
- Two Knights32008 / 33161
- Two Sets34593 / 37614
- Bit Strings40317 / 42587
- Trailing Zeros37747 / 40375
- Coin Piles33229 / 36682
- Palindrome Reorder30331 / 32341
- Gray Code18863 / 21576
- Tower of Hanoi17596 / 18350
- Creating Strings26163 / 26963
- Apple Division25364 / 29117
- Chessboard and Queens15072 / 15386
- Digit Queries10165 / 12231
- Grid Paths6282 / 8023
Sorting and Searching
- Distinct Numbers46289 / 50767
- Apartments33753 / 38361
- Ferris Wheel32102 / 35123
- Concert Tickets25688 / 30605
- Restaurant Customers26401 / 28828
- Movie Festival24833 / 26567
- Sum of Two Values29296 / 33435
- Maximum Subarray Sum28885 / 30394
- Stick Lengths25584 / 27032
- Missing Coin Sum17843 / 18573
- Collecting Numbers18501 / 20036
- Collecting Numbers II7365 / 9653
- Playlist19222 / 22437
- Towers19721 / 21338
- Traffic Lights15448 / 17423
- Josephus Problem I10498 / 11908
- Josephus Problem II6085 / 7937
- Nested Ranges Check5979 / 7025
- Nested Ranges Count4265 / 4920
- Room Allocation11233 / 13088
- Factory Machines14469 / 16229
- Tasks and Deadlines13084 / 13398
- Reading Books10424 / 11201
- Sum of Three Values15198 / 17235
- Sum of Four Values9631 / 10902
- Nearest Smaller Values12865 / 13378
- Subarray Sums I16598 / 17882
- Subarray Sums II15357 / 17541
- Subarray Divisibility13472 / 14870
- Subarray Distinct Values7651 / 8292
- Array Division12313 / 13074
- Sliding Window Median8144 / 9313
- Sliding Window Cost5682 / 6546
- Movie Festival II7027 / 8524
- Maximum Subarray Sum II6438 / 7729
Dynamic Programming
- Dice Combinations45688 / 48689
- Minimizing Coins39320 / 42588
- Coin Combinations I36166 / 39472
- Coin Combinations II30362 / 34864
- Removing Digits33567 / 34438
- Grid Paths31924 / 33004
- Book Shop28048 / 31383
- Array Description20269 / 22880
- Counting Towers11541 / 12252
- Edit Distance21046 / 22387
- Rectangle Cutting17558 / 19269
- Money Sums20935 / 21873
- Removal Game14956 / 16647
- Two Sets II16505 / 18028
- Increasing Subsequence16962 / 19287
- Projects11421 / 12973
- Elevator Rides6884 / 8863
- Counting Tilings3932 / 4330
- Counting Numbers5300 / 6052
Graph Algorithms
- Counting Rooms31209 / 33221
- Labyrinth20456 / 25434
- Building Roads27015 / 28176
- Message Route22961 / 24089
- Building Teams22018 / 23138
- Round Trip17100 / 18891
- Monsters10762 / 13270
- Shortest Routes I18333 / 20968
- Shortest Routes II15510 / 17015
- High Score7766 / 12778
- Flight Discount10815 / 13270
- Cycle Finding8039 / 10140
- Flight Routes7469 / 8428
- Round Trip II8971 / 10321
- Course Schedule12449 / 13007
- Longest Flight Route7680 / 10335
- Game Routes9002 / 9925
- Investigation6586 / 7166
- Planets Queries I5577 / 6821
- Planets Queries II2231 / 2775
- Planets Cycles3723 / 4194
- Road Reparation8917 / 9379
- Road Construction9400 / 9773
- Flight Routes Check7994 / 8837
- Planets and Kingdoms6443 / 6724
- Giant Pizza2594 / 2924
- Coin Collector4014 / 4556
- Mail Delivery3482 / 3879
- De Bruijn Sequence1871 / 1971
- Teleporters Path2755 / 3090
- Hamiltonian Flights3858 / 4394
- Knight's Tour1625 / 1928
- Download Speed2681 / 3809
- Police Chase2181 / 2507
- School Dance2403 / 2563
- Distinct Routes1537 / 2105
Range Queries
- Static Range Sum Queries21233 / 22230
- Static Range Minimum Queries15793 / 16913
- Dynamic Range Sum Queries16269 / 17040
- Dynamic Range Minimum Queries14791 / 15193
- Range Xor Queries14964 / 15192
- Range Update Queries11916 / 12847
- Forest Queries11687 / 12176
- Hotel Queries8536 / 9026
- List Removals7107 / 7512
- Salary Queries5256 / 6380
- Prefix Sum Queries4238 / 4640
- Pizzeria Queries3455 / 3587
- Subarray Sum Queries4403 / 4932
- Distinct Values Queries4128 / 5033
- Increasing Array Queries1490 / 1717
- Forest Queries II2842 / 3081
- Range Updates and Sums3399 / 4160
- Polynomial Queries2606 / 3066
- Range Queries and Copies1834 / 1989
Tree Algorithms
- Subordinates17557 / 19001
- Tree Matching9834 / 11615
- Tree Diameter14559 / 15611
- Tree Distances I10801 / 11730
- Tree Distances II8841 / 9239
- Company Queries I9762 / 10344
- Company Queries II9161 / 9683
- Distance Queries8550 / 9188
- Counting Paths5109 / 5478
- Subtree Queries6294 / 6749
- Path Queries5020 / 5317
- Path Queries II1773 / 2966
- Distinct Colors4785 / 5397
- Finding a Centroid3923 / 4106
- Fixed-Length Paths I1637 / 2353
- Fixed-Length Paths II666 / 1587
Mathematics
- Josephus Queries2552 / 3226
- Exponentiation14824 / 16030
- Exponentiation II10590 / 13052
- Counting Divisors12771 / 14637
- Common Divisors8571 / 10292
- Sum of Divisors4886 / 7498
- Divisor Analysis3168 / 4234
- Prime Multiples3444 / 4085
- Counting Coprime Pairs2172 / 2571
- Binomial Coefficients5989 / 6793
- Creating Strings II5030 / 5386
- Distributing Apples4914 / 5326
- Christmas Party3806 / 4140
- Bracket Sequences I2584 / 2867
- Bracket Sequences II1328 / 1533
- Counting Necklaces1286 / 1399
- Counting Grids1033 / 1105
- Fibonacci Numbers4383 / 5643
- Throwing Dice2375 / 2584
- Graph Paths I2168 / 2339
- Graph Paths II1818 / 1907
- Dice Probability2068 / 2197
- Moving Robots1040 / 1110
- Candy Lottery1597 / 1642
- Inversion Probability470 / 1436
- Stick Game2124 / 2184
- Nim Game I2680 / 2791
- Nim Game II2185 / 2284
- Stair Game1510 / 1656
- Grundy's Game966 / 1249
- Another Game1105 / 1205
String Algorithms
- Word Combinations3129 / 4809
- String Matching6256 / 9008
- Finding Borders4625 / 5184
- Finding Periods3158 / 3592
- Minimal Rotation1579 / 2584
- Longest Palindrome2381 / 3340
- Required Substring929 / 1510
- Palindrome Queries1147 / 1376
- Finding Patterns987 / 1461
- Counting Patterns890 / 1180
- Pattern Positions788 / 1009
- Distinct Substrings939 / 1132
- Repeating Substring957 / 1079
- String Functions910 / 961
- Substring Order I677 / 727
- Substring Order II443 / 562
- Substring Distribution614 / 672
Geometry
- Point Location Test4173 / 4810
- Line Segment Intersection2530 / 3304
- Polygon Area3031 / 3261
- Point in Polygon1663 / 2125
- Polygon Lattice Points1419 / 1475
- Minimum Euclidean Distance1294 / 1778
- Convex Hull2090 / 2544
Advanced Techniques
- Meet in the Middle3596 / 5552
- Hamming Distance1982 / 2148
- Beautiful Subgrids1394 / 1569
- Reachable Nodes1409 / 1530
- Reachability Queries968 / 1150
- Cut and Paste917 / 1032
- Substring Reversals803 / 883
- Reversals and Sums801 / 875
- Necessary Roads1210 / 1246
- Necessary Cities1131 / 1189
- Eulerian Subgraphs510 / 539
- Monster Game I733 / 806
- Monster Game II656 / 711
- Subarray Squares729 / 859
- Houses and Schools476 / 549
- Knuth Division558 / 632
- Apples and Bananas517 / 574
- One Bit Positions492 / 547
- Signal Processing460 / 503
- New Roads Queries1202 / 1468
- Dynamic Connectivity550 / 625
- Parcel Delivery439 / 500
- Task Assignment418 / 454
- Distinct Routes II349 / 407
Additional Problems
- Shortest Subsequence1993 / 2560
- Counting Bits2276 / 2947
- Swap Game1238 / 1596
- Prüfer Code875 / 971
- Acyclic Graph Edges1363 / 1455
- Strongly Connected Edges853 / 939
- Even Outdegree Edges778 / 908
- Multiplication Table2949 / 3367
- Advertisement2543 / 2713
- Special Substrings579 / 627
- Permutation Inversions624 / 690
- Maximum Xor Subarray1466 / 1605
- Movie Festival Queries644 / 721
- Chess Tournament730 / 835
- Tree Traversals700 / 785
- Network Renovation619 / 820
- Graph Girth1884 / 2201
- Intersection Points1154 / 1239
- Inverse Inversions632 / 663
- Monotone Subsequences429 / 477
- String Reorder510 / 563
- Stack Weights370 / 431
- Pyramid Array497 / 591
- Increasing Subsequence II1461 / 1585
- String Removals634 / 689
- Bit Inversions1483 / 1730
- Xor Pyramid780 / 993
- Writing Numbers509 / 550
- String Transform327 / 406
- Letter Pair Move Game117 / 172
- Maximum Building I1330 / 1394
- Sorting Methods533 / 570
- Cyclic Array662 / 762
- List of Sums300 / 403
- Increasing Array II501 / 570
- Food Division367 / 434
- Bit Problem967 / 1042
- Swap Round Sorting284 / 353
- Binary Subsequences148 / 235
- Tree Isomorphism I660 / 767
- Counting Sequences380 / 410
- Critical Cities251 / 398
- School Excursion864 / 922
- Coin Grid468 / 557
- Robot Path197 / 340
- Programmers and Artists316 / 405
- Course Schedule II1028 / 1460
- Removing Digits II127 / 269
- Coin Arrangement214 / 282
- Counting Bishops225 / 253
- Grid Puzzle I329 / 359
- Grid Puzzle II241 / 270
- Empty String925 / 1114
- Grid Paths502 / 624
- Bit Substrings224 / 280
- Reversal Sorting215 / 261
- Counting Reorders131 / 198
- Book Shop II653 / 743
- Network Breakdown618 / 657
- Visiting Cities458 / 595
- Missing Coin Sum Queries250 / 332
- Number Grid589 / 705
- Maximum Building II294 / 361
- Filling Trominos125 / 212
- Stick Divisions2357 / 2795
- Coding Company895 / 1140
- Flight Route Requests287 / 348
- Two Stacks Sorting94 / 324
- Tree Isomorphism II544 / 633
- Forbidden Cities454 / 594
- Area of Rectangles686 / 773
- Grid Completion132 / 174
- Creating Offices257 / 335
- Permutations II576 / 659
- Functional Graph Distribution146 / 183
- New Flight Routes202 / 485
- Grid Path Construction66 / 238