General
Introductory Problems
- Weird Algorithm98818 / 103509
- Missing Number84086 / 88706
- Repetitions73418 / 76925
- Increasing Array68519 / 71409
- Permutations60254 / 62320
- Number Spiral42646 / 46517
- Two Knights31977 / 33130
- Two Sets34566 / 37583
- Bit Strings40280 / 42546
- Trailing Zeros37713 / 40341
- Coin Piles33197 / 36648
- Palindrome Reorder30309 / 32319
- Gray Code18844 / 21550
- Tower of Hanoi17575 / 18329
- Creating Strings26138 / 26937
- Apple Division25348 / 29098
- Chessboard and Queens15060 / 15375
- Digit Queries10158 / 12221
- Grid Paths6273 / 8012
Sorting and Searching
- Distinct Numbers46249 / 50727
- Apartments33720 / 38323
- Ferris Wheel32073 / 35096
- Concert Tickets25661 / 30575
- Restaurant Customers26377 / 28804
- Movie Festival24820 / 26550
- Sum of Two Values29270 / 33406
- Maximum Subarray Sum28865 / 30372
- Stick Lengths25567 / 27014
- Missing Coin Sum17827 / 18558
- Collecting Numbers18488 / 20023
- Collecting Numbers II7363 / 9647
- Playlist19213 / 22424
- Towers19713 / 21329
- Traffic Lights15439 / 17413
- Josephus Problem I10489 / 11899
- Josephus Problem II6083 / 7932
- Nested Ranges Check5970 / 7018
- Nested Ranges Count4262 / 4917
- Room Allocation11229 / 13083
- Factory Machines14432 / 16190
- Tasks and Deadlines13067 / 13381
- Reading Books10417 / 11194
- Sum of Three Values15181 / 17213
- Sum of Four Values9623 / 10893
- Nearest Smaller Values12858 / 13369
- Subarray Sums I16582 / 17865
- Subarray Sums II15344 / 17527
- Subarray Divisibility13463 / 14861
- Subarray Distinct Values7643 / 8284
- Array Division12301 / 13061
- Sliding Window Median8129 / 9294
- Sliding Window Cost5680 / 6544
- Movie Festival II7016 / 8514
- Maximum Subarray Sum II6427 / 7715
Dynamic Programming
- Dice Combinations45642 / 48639
- Minimizing Coins39282 / 42546
- Coin Combinations I36130 / 39437
- Coin Combinations II30321 / 34826
- Removing Digits33523 / 34393
- Grid Paths31888 / 32967
- Book Shop28017 / 31352
- Array Description20251 / 22863
- Counting Towers11524 / 12233
- Edit Distance21020 / 22366
- Rectangle Cutting17537 / 19247
- Money Sums20915 / 21850
- Removal Game14942 / 16630
- Two Sets II16493 / 18014
- Increasing Subsequence16951 / 19276
- Projects11412 / 12966
- Elevator Rides6875 / 8854
- Counting Tilings3925 / 4322
- Counting Numbers5295 / 6047
Graph Algorithms
- Counting Rooms31184 / 33196
- Labyrinth20435 / 25408
- Building Roads26988 / 28146
- Message Route22939 / 24061
- Building Teams22000 / 23121
- Round Trip17076 / 18868
- Monsters10748 / 13252
- Shortest Routes I18300 / 20934
- Shortest Routes II15488 / 16991
- High Score7753 / 12758
- Flight Discount10800 / 13253
- Cycle Finding8032 / 10131
- Flight Routes7466 / 8425
- Round Trip II8962 / 10311
- Course Schedule12437 / 12992
- Longest Flight Route7674 / 10323
- Game Routes8994 / 9918
- Investigation6576 / 7155
- Planets Queries I5569 / 6811
- Planets Queries II2229 / 2773
- Planets Cycles3718 / 4189
- Road Reparation8909 / 9370
- Road Construction9391 / 9764
- Flight Routes Check7985 / 8828
- Planets and Kingdoms6437 / 6717
- Giant Pizza2593 / 2924
- Coin Collector4013 / 4556
- Mail Delivery3478 / 3875
- De Bruijn Sequence1869 / 1969
- Teleporters Path2753 / 3089
- Hamiltonian Flights3858 / 4393
- Knight's Tour1625 / 1927
- Download Speed2677 / 3806
- Police Chase2181 / 2507
- School Dance2401 / 2561
- Distinct Routes1536 / 2104
Range Queries
- Static Range Sum Queries21212 / 22208
- Static Range Minimum Queries15778 / 16898
- Dynamic Range Sum Queries16253 / 17024
- Dynamic Range Minimum Queries14779 / 15178
- Range Xor Queries14948 / 15176
- Range Update Queries11902 / 12833
- Forest Queries11680 / 12170
- Hotel Queries8523 / 9011
- List Removals7097 / 7502
- Salary Queries5247 / 6370
- Prefix Sum Queries4230 / 4632
- Pizzeria Queries3447 / 3579
- Subarray Sum Queries4401 / 4930
- Distinct Values Queries4123 / 5027
- Increasing Array Queries1489 / 1716
- Forest Queries II2839 / 3079
- Range Updates and Sums3397 / 4157
- Polynomial Queries2604 / 3063
- Range Queries and Copies1833 / 1988
Tree Algorithms
- Subordinates17540 / 18985
- Tree Matching9825 / 11599
- Tree Diameter14538 / 15589
- Tree Distances I10791 / 11716
- Tree Distances II8833 / 9231
- Company Queries I9748 / 10331
- Company Queries II9152 / 9673
- Distance Queries8546 / 9184
- Counting Paths5107 / 5476
- Subtree Queries6286 / 6741
- Path Queries5017 / 5314
- Path Queries II1772 / 2963
- Distinct Colors4782 / 5394
- Finding a Centroid3917 / 4100
- Fixed-Length Paths I1627 / 2345
- Fixed-Length Paths II666 / 1585
Mathematics
- Josephus Queries2547 / 3220
- Exponentiation14817 / 16020
- Exponentiation II10581 / 13044
- Counting Divisors12755 / 14620
- Common Divisors8560 / 10278
- Sum of Divisors4877 / 7485
- Divisor Analysis3165 / 4230
- Prime Multiples3441 / 4082
- Counting Coprime Pairs2170 / 2569
- Binomial Coefficients5984 / 6787
- Creating Strings II5025 / 5380
- Distributing Apples4910 / 5322
- Christmas Party3799 / 4133
- Bracket Sequences I2580 / 2863
- Bracket Sequences II1326 / 1531
- Counting Necklaces1285 / 1397
- Counting Grids1032 / 1104
- Fibonacci Numbers4377 / 5636
- Throwing Dice2370 / 2579
- Graph Paths I2166 / 2337
- Graph Paths II1816 / 1904
- Dice Probability2066 / 2195
- Moving Robots1036 / 1106
- Candy Lottery1592 / 1637
- Inversion Probability467 / 1431
- Stick Game2123 / 2183
- Nim Game I2678 / 2789
- Nim Game II2182 / 2281
- Stair Game1508 / 1654
- Grundy's Game964 / 1247
- Another Game1104 / 1204
String Algorithms
- Word Combinations3120 / 4796
- String Matching6239 / 8992
- Finding Borders4621 / 5179
- Finding Periods3156 / 3590
- Minimal Rotation1577 / 2582
- Longest Palindrome2379 / 3338
- Required Substring929 / 1510
- Palindrome Queries1147 / 1375
- Finding Patterns986 / 1459
- Counting Patterns889 / 1179
- Pattern Positions787 / 1008
- Distinct Substrings938 / 1131
- Repeating Substring957 / 1079
- String Functions909 / 960
- Substring Order I676 / 726
- Substring Order II443 / 562
- Substring Distribution614 / 672
Geometry
- Point Location Test4168 / 4805
- Line Segment Intersection2529 / 3302
- Polygon Area3029 / 3259
- Point in Polygon1663 / 2123
- Polygon Lattice Points1418 / 1474
- Minimum Euclidean Distance1293 / 1778
- Convex Hull2086 / 2538
Advanced Techniques
- Meet in the Middle3593 / 5550
- Hamming Distance1979 / 2145
- Beautiful Subgrids1393 / 1569
- Reachable Nodes1408 / 1529
- Reachability Queries968 / 1150
- Cut and Paste917 / 1032
- Substring Reversals802 / 882
- Reversals and Sums799 / 873
- Necessary Roads1209 / 1245
- Necessary Cities1130 / 1188
- Eulerian Subgraphs509 / 538
- Monster Game I732 / 805
- Monster Game II655 / 710
- Subarray Squares729 / 859
- Houses and Schools475 / 548
- Knuth Division557 / 630
- Apples and Bananas516 / 573
- One Bit Positions491 / 546
- Signal Processing459 / 502
- New Roads Queries1202 / 1467
- Dynamic Connectivity548 / 623
- Parcel Delivery439 / 500
- Task Assignment418 / 454
- Distinct Routes II349 / 407
Additional Problems
- Shortest Subsequence1989 / 2556
- Counting Bits2275 / 2946
- Swap Game1235 / 1592
- Prüfer Code874 / 969
- Acyclic Graph Edges1363 / 1455
- Strongly Connected Edges853 / 939
- Even Outdegree Edges777 / 907
- Multiplication Table2943 / 3360
- Advertisement2539 / 2709
- Special Substrings579 / 627
- Permutation Inversions623 / 689
- Maximum Xor Subarray1463 / 1602
- Movie Festival Queries644 / 721
- Chess Tournament726 / 831
- Tree Traversals699 / 785
- Network Renovation617 / 818
- Graph Girth1883 / 2200
- Intersection Points1153 / 1239
- Inverse Inversions632 / 663
- Monotone Subsequences429 / 476
- String Reorder510 / 563
- Stack Weights370 / 431
- Pyramid Array497 / 591
- Increasing Subsequence II1459 / 1583
- String Removals634 / 689
- Bit Inversions1479 / 1726
- Xor Pyramid779 / 990
- Writing Numbers509 / 550
- String Transform327 / 406
- Letter Pair Move Game116 / 171
- Maximum Building I1329 / 1393
- Sorting Methods531 / 568
- Cyclic Array662 / 762
- List of Sums300 / 402
- Increasing Array II499 / 568
- Food Division366 / 433
- Bit Problem964 / 1039
- Swap Round Sorting282 / 351
- Binary Subsequences148 / 235
- Tree Isomorphism I660 / 767
- Counting Sequences379 / 409
- Critical Cities251 / 397
- School Excursion863 / 921
- Coin Grid467 / 556
- Robot Path197 / 340
- Programmers and Artists315 / 404
- Course Schedule II1025 / 1457
- Removing Digits II127 / 269
- Coin Arrangement214 / 282
- Counting Bishops225 / 253
- Grid Puzzle I329 / 359
- Grid Puzzle II241 / 270
- Empty String924 / 1112
- Grid Paths502 / 624
- Bit Substrings224 / 280
- Reversal Sorting215 / 261
- Counting Reorders131 / 198
- Book Shop II651 / 741
- Network Breakdown618 / 657
- Visiting Cities457 / 594
- Missing Coin Sum Queries250 / 332
- Number Grid589 / 705
- Maximum Building II293 / 360
- Filling Trominos125 / 212
- Stick Divisions2355 / 2794
- Coding Company892 / 1137
- Flight Route Requests285 / 347
- Two Stacks Sorting94 / 324
- Tree Isomorphism II544 / 633
- Forbidden Cities454 / 594
- Area of Rectangles686 / 773
- Grid Completion132 / 174
- Creating Offices257 / 335
- Permutations II575 / 658
- Functional Graph Distribution146 / 183
- New Flight Routes202 / 485
- Grid Path Construction66 / 238