General
Introductory Problems
- Weird Algorithm98321 / 102989
- Missing Number83661 / 88257
- Repetitions73033 / 76519
- Increasing Array68175 / 71056
- Permutations59937 / 61995
- Number Spiral42404 / 46251
- Two Knights31817 / 32963
- Two Sets34359 / 37363
- Bit Strings40047 / 42300
- Trailing Zeros37511 / 40120
- Coin Piles33020 / 36442
- Palindrome Reorder30156 / 32160
- Gray Code18740 / 21433
- Tower of Hanoi17469 / 18220
- Creating Strings25985 / 26780
- Apple Division25204 / 28951
- Chessboard and Queens14981 / 15294
- Digit Queries10093 / 12145
- Grid Paths6239 / 7973
Sorting and Searching
- Distinct Numbers45998 / 50463
- Apartments33534 / 38116
- Ferris Wheel31894 / 34898
- Concert Tickets25513 / 30400
- Restaurant Customers26224 / 28635
- Movie Festival24670 / 26388
- Sum of Two Values29088 / 33211
- Maximum Subarray Sum28699 / 30199
- Stick Lengths25418 / 26857
- Missing Coin Sum17719 / 18447
- Collecting Numbers18374 / 19906
- Collecting Numbers II7318 / 9583
- Playlist19118 / 22313
- Towers19605 / 21212
- Traffic Lights15360 / 17320
- Josephus Problem I10406 / 11812
- Josephus Problem II6041 / 7880
- Nested Ranges Check5922 / 6967
- Nested Ranges Count4228 / 4879
- Room Allocation11166 / 13013
- Factory Machines14323 / 16072
- Tasks and Deadlines12962 / 13277
- Reading Books10346 / 11117
- Sum of Three Values15084 / 17108
- Sum of Four Values9564 / 10829
- Nearest Smaller Values12780 / 13291
- Subarray Sums I16473 / 17750
- Subarray Sums II15235 / 17416
- Subarray Divisibility13378 / 14770
- Subarray Distinct Values7577 / 8216
- Array Division12199 / 12953
- Sliding Window Median8066 / 9214
- Sliding Window Cost5646 / 6507
- Movie Festival II6970 / 8459
- Maximum Subarray Sum II6371 / 7654
Dynamic Programming
- Dice Combinations45354 / 48344
- Minimizing Coins39030 / 42266
- Coin Combinations I35914 / 39193
- Coin Combinations II30141 / 34617
- Removing Digits33347 / 34209
- Grid Paths31701 / 32774
- Book Shop27854 / 31175
- Array Description20127 / 22722
- Counting Towers11432 / 12139
- Edit Distance20890 / 22223
- Rectangle Cutting17435 / 19125
- Money Sums20798 / 21728
- Removal Game14860 / 16546
- Two Sets II16399 / 17911
- Increasing Subsequence16867 / 19172
- Projects11348 / 12893
- Elevator Rides6818 / 8782
- Counting Tilings3896 / 4292
- Counting Numbers5263 / 6010
Graph Algorithms
- Counting Rooms30979 / 32981
- Labyrinth20322 / 25260
- Building Roads26811 / 27955
- Message Route22777 / 23894
- Building Teams21866 / 22980
- Round Trip16971 / 18752
- Monsters10662 / 13149
- Shortest Routes I18222 / 20724
- Shortest Routes II15355 / 16836
- High Score7665 / 12648
- Flight Discount10704 / 13134
- Cycle Finding7956 / 10037
- Flight Routes7408 / 8359
- Round Trip II8893 / 10236
- Course Schedule12351 / 12895
- Longest Flight Route7608 / 10242
- Game Routes8935 / 9849
- Investigation6533 / 7106
- Planets Queries I5536 / 6772
- Planets Queries II2220 / 2758
- Planets Cycles3697 / 4162
- Road Reparation8830 / 9287
- Road Construction9299 / 9670
- Flight Routes Check7938 / 8776
- Planets and Kingdoms6400 / 6679
- Giant Pizza2574 / 2901
- Coin Collector3984 / 4526
- Mail Delivery3439 / 3833
- De Bruijn Sequence1859 / 1960
- Teleporters Path2735 / 3068
- Hamiltonian Flights3821 / 4360
- Knight's Tour1616 / 1916
- Download Speed2650 / 3776
- Police Chase2166 / 2489
- School Dance2388 / 2548
- Distinct Routes1529 / 2093
Range Queries
- Static Range Sum Queries21051 / 22044
- Static Range Minimum Queries15662 / 16778
- Dynamic Range Sum Queries16132 / 16892
- Dynamic Range Minimum Queries14674 / 15065
- Range Xor Queries14841 / 15067
- Range Update Queries11811 / 12739
- Forest Queries11604 / 12088
- Hotel Queries8469 / 8951
- List Removals7036 / 7436
- Salary Queries5199 / 6301
- Prefix Sum Queries4196 / 4596
- Pizzeria Queries3417 / 3547
- Subarray Sum Queries4359 / 4888
- Distinct Values Queries4088 / 4985
- Increasing Array Queries1483 / 1707
- Forest Queries II2824 / 3061
- Range Updates and Sums3375 / 4127
- Polynomial Queries2590 / 3045
- Range Queries and Copies1820 / 1975
Tree Algorithms
- Subordinates17450 / 18891
- Tree Matching9771 / 11537
- Tree Diameter14456 / 15503
- Tree Distances I10717 / 11638
- Tree Distances II8782 / 9177
- Company Queries I9690 / 10274
- Company Queries II9098 / 9620
- Distance Queries8503 / 9130
- Counting Paths5071 / 5437
- Subtree Queries6239 / 6688
- Path Queries4985 / 5271
- Path Queries II1729 / 2908
- Distinct Colors4742 / 5354
- Finding a Centroid3877 / 4060
- Fixed-Length Paths I1590 / 2299
- Fixed-Length Paths II654 / 1571
Mathematics
- Josephus Queries2528 / 3198
- Exponentiation14731 / 15924
- Exponentiation II10522 / 12978
- Counting Divisors12662 / 14520
- Common Divisors8504 / 10213
- Sum of Divisors4853 / 7444
- Divisor Analysis3147 / 4207
- Prime Multiples3417 / 4055
- Counting Coprime Pairs2157 / 2555
- Binomial Coefficients5947 / 6745
- Creating Strings II4986 / 5339
- Distributing Apples4873 / 5282
- Christmas Party3775 / 4107
- Bracket Sequences I2560 / 2842
- Bracket Sequences II1314 / 1519
- Counting Necklaces1272 / 1384
- Counting Grids1023 / 1095
- Fibonacci Numbers4350 / 5597
- Throwing Dice2355 / 2564
- Graph Paths I2152 / 2320
- Graph Paths II1805 / 1890
- Dice Probability2055 / 2183
- Moving Robots1032 / 1102
- Candy Lottery1582 / 1626
- Inversion Probability456 / 1420
- Stick Game2111 / 2171
- Nim Game I2656 / 2765
- Nim Game II2158 / 2254
- Stair Game1499 / 1645
- Grundy's Game958 / 1240
- Another Game1094 / 1192
String Algorithms
- Word Combinations3103 / 4763
- String Matching6193 / 8932
- Finding Borders4600 / 5157
- Finding Periods3137 / 3569
- Minimal Rotation1570 / 2573
- Longest Palindrome2364 / 3317
- Required Substring919 / 1501
- Palindrome Queries1139 / 1365
- Finding Patterns983 / 1453
- Counting Patterns886 / 1176
- Pattern Positions785 / 1006
- Distinct Substrings937 / 1130
- Repeating Substring955 / 1075
- String Functions908 / 958
- Substring Order I673 / 723
- Substring Order II441 / 561
- Substring Distribution611 / 669
Geometry
- Point Location Test4122 / 4760
- Line Segment Intersection2575 / 3268
- Polygon Area3002 / 3227
- Point in Polygon1648 / 2104
- Polygon Lattice Points1411 / 1463
- Minimum Euclidean Distance1281 / 1765
- Convex Hull2064 / 2512
Advanced Techniques
- Meet in the Middle3560 / 5512
- Hamming Distance1963 / 2126
- Beautiful Subgrids1385 / 1559
- Reachable Nodes1390 / 1511
- Reachability Queries962 / 1142
- Cut and Paste906 / 1020
- Substring Reversals790 / 868
- Reversals and Sums790 / 863
- Necessary Roads1198 / 1234
- Necessary Cities1118 / 1176
- Eulerian Subgraphs504 / 533
- Monster Game I728 / 801
- Monster Game II652 / 707
- Subarray Squares721 / 850
- Houses and Schools473 / 545
- Knuth Division553 / 625
- Apples and Bananas514 / 571
- One Bit Positions488 / 542
- Signal Processing456 / 498
- New Roads Queries1199 / 1462
- Dynamic Connectivity545 / 620
- Parcel Delivery438 / 499
- Task Assignment416 / 452
- Distinct Routes II349 / 407
Additional Problems
- Shortest Subsequence1972 / 2539
- Counting Bits2268 / 2935
- Swap Game1227 / 1582
- Prüfer Code872 / 968
- Acyclic Graph Edges1357 / 1448
- Strongly Connected Edges845 / 932
- Even Outdegree Edges768 / 898
- Multiplication Table2906 / 3320
- Advertisement2521 / 2690
- Special Substrings576 / 624
- Permutation Inversions621 / 688
- Maximum Xor Subarray1450 / 1587
- Movie Festival Queries643 / 719
- Chess Tournament722 / 826
- Tree Traversals696 / 782
- Network Renovation613 / 815
- Graph Girth1877 / 2187
- Intersection Points1142 / 1227
- Inverse Inversions631 / 662
- Monotone Subsequences426 / 473
- String Reorder506 / 559
- Stack Weights369 / 430
- Pyramid Array496 / 590
- Increasing Subsequence II1447 / 1569
- String Removals632 / 687
- Bit Inversions1465 / 1713
- Xor Pyramid775 / 986
- Writing Numbers508 / 549
- String Transform326 / 405
- Letter Pair Move Game114 / 170
- Maximum Building I1325 / 1389
- Sorting Methods529 / 566
- Cyclic Array656 / 756
- List of Sums299 / 401
- Increasing Array II496 / 565
- Food Division365 / 432
- Bit Problem951 / 1027
- Swap Round Sorting282 / 351
- Binary Subsequences148 / 235
- Tree Isomorphism I658 / 766
- Counting Sequences378 / 408
- Critical Cities249 / 395
- School Excursion852 / 910
- Coin Grid463 / 552
- Robot Path197 / 340
- Programmers and Artists313 / 402
- Course Schedule II1022 / 1454
- Removing Digits II126 / 268
- Coin Arrangement214 / 282
- Counting Bishops224 / 252
- Grid Puzzle I327 / 357
- Grid Puzzle II241 / 270
- Empty String918 / 1105
- Grid Paths501 / 622
- Bit Substrings224 / 279
- Reversal Sorting214 / 260
- Counting Reorders131 / 198
- Book Shop II649 / 738
- Network Breakdown612 / 652
- Visiting Cities451 / 586
- Missing Coin Sum Queries250 / 331
- Number Grid589 / 705
- Maximum Building II291 / 358
- Filling Trominos125 / 212
- Stick Divisions2335 / 2774
- Coding Company883 / 1128
- Flight Route Requests285 / 345
- Two Stacks Sorting94 / 323
- Tree Isomorphism II541 / 631
- Forbidden Cities452 / 591
- Area of Rectangles678 / 765
- Grid Completion132 / 174
- Creating Offices256 / 334
- Permutations II572 / 655
- Functional Graph Distribution146 / 183
- New Flight Routes201 / 483
- Grid Path Construction63 / 233