General
Introductory Problems
- Weird Algorithm99842 / 104594
- Missing Number84994 / 89666
- Repetitions74238 / 77764
- Increasing Array69318 / 72234
- Permutations60956 / 63041
- Number Spiral43134 / 47049
- Two Knights32348 / 33512
- Two Sets34967 / 38009
- Bit Strings40726 / 43014
- Trailing Zeros38105 / 40760
- Coin Piles33566 / 37052
- Palindrome Reorder30684 / 32716
- Gray Code19110 / 21859
- Tower of Hanoi17811 / 18577
- Creating Strings26451 / 27259
- Apple Division25678 / 29454
- Chessboard and Queens15246 / 15564
- Digit Queries10312 / 12404
- Grid Paths6355 / 8133
Sorting and Searching
- Distinct Numbers46864 / 51371
- Apartments34175 / 38836
- Ferris Wheel32513 / 35572
- Concert Tickets26032 / 31015
- Restaurant Customers26768 / 29219
- Movie Festival25163 / 26909
- Sum of Two Values29679 / 33864
- Maximum Subarray Sum29241 / 30765
- Stick Lengths25911 / 27369
- Missing Coin Sum18107 / 18851
- Collecting Numbers18763 / 20326
- Collecting Numbers II7477 / 9793
- Playlist19445 / 22690
- Towers19940 / 21582
- Traffic Lights15629 / 17617
- Josephus Problem I10655 / 12084
- Josephus Problem II6160 / 8043
- Nested Ranges Check6050 / 7118
- Nested Ranges Count4302 / 4976
- Room Allocation11381 / 13251
- Factory Machines14751 / 16530
- Tasks and Deadlines13222 / 13537
- Reading Books10540 / 11329
- Sum of Three Values15380 / 17444
- Sum of Four Values9753 / 11032
- Nearest Smaller Values12992 / 13508
- Subarray Sums I16819 / 18112
- Subarray Sums II15538 / 17740
- Subarray Divisibility13628 / 15039
- Subarray Distinct Values7778 / 8426
- Array Division12482 / 13254
- Sliding Window Median8260 / 9450
- Sliding Window Cost5743 / 6613
- Movie Festival II7104 / 8611
- Maximum Subarray Sum II6509 / 7815
Dynamic Programming
- Dice Combinations46249 / 49285
- Minimizing Coins39804 / 43101
- Coin Combinations I36586 / 39932
- Coin Combinations II30719 / 35267
- Removing Digits33964 / 34843
- Grid Paths32288 / 33386
- Book Shop28404 / 31772
- Array Description20514 / 23149
- Counting Towers11693 / 12414
- Edit Distance21272 / 22627
- Rectangle Cutting17747 / 19476
- Money Sums21186 / 22136
- Removal Game15119 / 16826
- Two Sets II16699 / 18245
- Increasing Subsequence17163 / 19512
- Projects11534 / 13103
- Elevator Rides6985 / 8980
- Counting Tilings3993 / 4397
- Counting Numbers5380 / 6138
Graph Algorithms
- Counting Rooms31546 / 33581
- Labyrinth20698 / 25730
- Building Roads27305 / 28477
- Message Route23200 / 24337
- Building Teams22267 / 23410
- Round Trip17284 / 19095
- Monsters10911 / 13439
- Shortest Routes I18543 / 21190
- Shortest Routes II15658 / 17181
- High Score7872 / 12919
- Flight Discount10946 / 13423
- Cycle Finding8128 / 10242
- Flight Routes7556 / 8522
- Round Trip II9079 / 10435
- Course Schedule12582 / 13153
- Longest Flight Route7795 / 10464
- Game Routes9090 / 10021
- Investigation6675 / 7267
- Planets Queries I5644 / 6892
- Planets Queries II2261 / 2808
- Planets Cycles3772 / 4252
- Road Reparation9028 / 9496
- Road Construction9520 / 9898
- Flight Routes Check8094 / 8952
- Planets and Kingdoms6524 / 6809
- Giant Pizza2659 / 2993
- Coin Collector4072 / 4617
- Mail Delivery3532 / 3936
- De Bruijn Sequence1900 / 2001
- Teleporters Path2802 / 3137
- Hamiltonian Flights3915 / 4459
- Knight's Tour1653 / 1960
- Download Speed2759 / 3891
- Police Chase2216 / 2545
- School Dance2438 / 2600
- Distinct Routes1589 / 2159
Range Queries
- Static Range Sum Queries21510 / 22516
- Static Range Minimum Queries15989 / 17121
- Dynamic Range Sum Queries16480 / 17260
- Dynamic Range Minimum Queries14996 / 15408
- Range Xor Queries15144 / 15379
- Range Update Queries12083 / 13036
- Forest Queries11830 / 12319
- Hotel Queries8658 / 9155
- List Removals7216 / 7629
- Salary Queries5336 / 6484
- Prefix Sum Queries4286 / 4696
- Pizzeria Queries3502 / 3634
- Subarray Sum Queries4456 / 4985
- Distinct Values Queries4177 / 5091
- Increasing Array Queries1509 / 1740
- Forest Queries II2871 / 3113
- Range Updates and Sums3441 / 4218
- Polynomial Queries2629 / 3101
- Range Queries and Copies1851 / 2009
Tree Algorithms
- Subordinates17778 / 19244
- Tree Matching9930 / 11734
- Tree Diameter14714 / 15765
- Tree Distances I10910 / 11849
- Tree Distances II8944 / 9351
- Company Queries I9875 / 10466
- Company Queries II9270 / 9802
- Distance Queries8654 / 9297
- Counting Paths5166 / 5543
- Subtree Queries6387 / 6844
- Path Queries5099 / 5397
- Path Queries II1816 / 3010
- Distinct Colors4856 / 5471
- Finding a Centroid3974 / 4158
- Fixed-Length Paths I1671 / 2388
- Fixed-Length Paths II685 / 1615
Mathematics
- Josephus Queries2576 / 3262
- Exponentiation14981 / 16206
- Exponentiation II10729 / 13210
- Counting Divisors12942 / 14845
- Common Divisors8669 / 10412
- Sum of Divisors4932 / 7559
- Divisor Analysis3213 / 4295
- Prime Multiples3490 / 4142
- Counting Coprime Pairs2196 / 2603
- Binomial Coefficients6052 / 6863
- Creating Strings II5076 / 5436
- Distributing Apples4957 / 5384
- Christmas Party3841 / 4177
- Bracket Sequences I2616 / 2903
- Bracket Sequences II1346 / 1556
- Counting Necklaces1301 / 1419
- Counting Grids1048 / 1122
- Fibonacci Numbers4429 / 5711
- Throwing Dice2404 / 2613
- Graph Paths I2194 / 2367
- Graph Paths II1837 / 1928
- Dice Probability2093 / 2222
- Moving Robots1051 / 1122
- Candy Lottery1619 / 1665
- Inversion Probability481 / 1448
- Stick Game2154 / 2215
- Nim Game I2720 / 2841
- Nim Game II2218 / 2319
- Stair Game1528 / 1676
- Grundy's Game986 / 1274
- Another Game1122 / 1224
String Algorithms
- Word Combinations3183 / 4879
- String Matching6391 / 9151
- Finding Borders4690 / 5250
- Finding Periods3213 / 3657
- Minimal Rotation1598 / 2618
- Longest Palindrome2425 / 3396
- Required Substring948 / 1537
- Palindrome Queries1168 / 1405
- Finding Patterns1010 / 1490
- Counting Patterns910 / 1204
- Pattern Positions804 / 1027
- Distinct Substrings957 / 1156
- Repeating Substring974 / 1098
- String Functions929 / 982
- Substring Order I691 / 742
- Substring Order II449 / 571
- Substring Distribution625 / 684
Geometry
- Point Location Test4230 / 4874
- Line Segment Intersection2571 / 3352
- Polygon Area3076 / 3308
- Point in Polygon1690 / 2157
- Polygon Lattice Points1443 / 1500
- Minimum Euclidean Distance1319 / 1805
- Convex Hull2132 / 2587
Advanced Techniques
- Meet in the Middle3653 / 5624
- Hamming Distance2004 / 2171
- Beautiful Subgrids1415 / 1592
- Reachable Nodes1431 / 1553
- Reachability Queries988 / 1172
- Cut and Paste935 / 1055
- Substring Reversals822 / 904
- Reversals and Sums821 / 899
- Necessary Roads1228 / 1265
- Necessary Cities1144 / 1204
- Eulerian Subgraphs515 / 545
- Monster Game I745 / 819
- Monster Game II667 / 724
- Subarray Squares738 / 870
- Houses and Schools483 / 559
- Knuth Division566 / 641
- Apples and Bananas526 / 583
- One Bit Positions504 / 561
- Signal Processing469 / 514
- New Roads Queries1225 / 1495
- Dynamic Connectivity562 / 644
- Parcel Delivery446 / 508
- Task Assignment429 / 468
- Distinct Routes II355 / 414
Additional Problems
- Shortest Subsequence2020 / 2592
- Counting Bits2306 / 2979
- Swap Game1265 / 1624
- Prüfer Code890 / 986
- Acyclic Graph Edges1385 / 1480
- Strongly Connected Edges873 / 961
- Even Outdegree Edges793 / 926
- Multiplication Table3010 / 3439
- Advertisement2585 / 2756
- Special Substrings596 / 646
- Permutation Inversions639 / 709
- Maximum Xor Subarray1485 / 1628
- Movie Festival Queries655 / 733
- Chess Tournament737 / 843
- Tree Traversals709 / 797
- Network Renovation626 / 830
- Graph Girth1921 / 2241
- Intersection Points1174 / 1265
- Inverse Inversions647 / 678
- Monotone Subsequences437 / 487
- String Reorder516 / 570
- Stack Weights376 / 440
- Pyramid Array500 / 597
- Increasing Subsequence II1488 / 1615
- String Removals646 / 702
- Bit Inversions1509 / 1757
- Xor Pyramid791 / 1009
- Writing Numbers510 / 554
- String Transform329 / 410
- Letter Pair Move Game119 / 176
- Maximum Building I1347 / 1414
- Sorting Methods538 / 577
- Cyclic Array673 / 774
- List of Sums302 / 406
- Increasing Array II511 / 583
- Food Division369 / 438
- Bit Problem981 / 1059
- Swap Round Sorting287 / 357
- Binary Subsequences149 / 239
- Tree Isomorphism I667 / 775
- Counting Sequences384 / 415
- Critical Cities258 / 403
- School Excursion874 / 933
- Coin Grid471 / 563
- Robot Path199 / 345
- Programmers and Artists317 / 407
- Course Schedule II1044 / 1481
- Removing Digits II127 / 274
- Coin Arrangement216 / 286
- Counting Bishops228 / 257
- Grid Puzzle I334 / 365
- Grid Puzzle II247 / 277
- Empty String936 / 1127
- Grid Paths508 / 633
- Bit Substrings236 / 294
- Reversal Sorting219 / 267
- Counting Reorders133 / 201
- Book Shop II661 / 753
- Network Breakdown627 / 667
- Visiting Cities461 / 601
- Missing Coin Sum Queries256 / 342
- Number Grid596 / 715
- Maximum Building II295 / 363
- Filling Trominos128 / 219
- Stick Divisions2391 / 2834
- Coding Company904 / 1153
- Flight Route Requests296 / 359
- Two Stacks Sorting95 / 328
- Tree Isomorphism II549 / 638
- Forbidden Cities457 / 599
- Area of Rectangles692 / 780
- Grid Completion133 / 177
- Creating Offices259 / 337
- Permutations II583 / 667
- Functional Graph Distribution147 / 185
- New Flight Routes205 / 496
- Grid Path Construction67 / 241