General
Introductory Problems
- Weird Algorithm98791 / 103477
- Missing Number84061 / 88685
- Repetitions73390 / 76897
- Increasing Array68497 / 71389
- Permutations60225 / 62291
- Number Spiral42629 / 46497
- Two Knights31964 / 33116
- Two Sets34549 / 37566
- Bit Strings40255 / 42520
- Trailing Zeros37688 / 40318
- Coin Piles33172 / 36622
- Palindrome Reorder30290 / 32299
- Gray Code18834 / 21538
- Tower of Hanoi17562 / 18318
- Creating Strings26127 / 26926
- Apple Division25334 / 29087
- Chessboard and Queens15054 / 15368
- Digit Queries10153 / 12215
- Grid Paths6269 / 8010
Sorting and Searching
- Distinct Numbers46226 / 50701
- Apartments33705 / 38312
- Ferris Wheel32063 / 35086
- Concert Tickets25653 / 30564
- Restaurant Customers26362 / 28788
- Movie Festival24806 / 26534
- Sum of Two Values29251 / 33387
- Maximum Subarray Sum28852 / 30357
- Stick Lengths25548 / 26994
- Missing Coin Sum17816 / 18546
- Collecting Numbers18471 / 20008
- Collecting Numbers II7360 / 9642
- Playlist19208 / 22416
- Towers19702 / 21319
- Traffic Lights15435 / 17407
- Josephus Problem I10488 / 11897
- Josephus Problem II6078 / 7929
- Nested Ranges Check5967 / 7014
- Nested Ranges Count4260 / 4915
- Room Allocation11225 / 13078
- Factory Machines14425 / 16182
- Tasks and Deadlines13061 / 13375
- Reading Books10411 / 11188
- Sum of Three Values15177 / 17206
- Sum of Four Values9621 / 10890
- Nearest Smaller Values12851 / 13362
- Subarray Sums I16567 / 17850
- Subarray Sums II15335 / 17519
- Subarray Divisibility13459 / 14858
- Subarray Distinct Values7638 / 8277
- Array Division12297 / 13056
- Sliding Window Median8124 / 9290
- Sliding Window Cost5675 / 6540
- Movie Festival II7011 / 8506
- Maximum Subarray Sum II6419 / 7706
Dynamic Programming
- Dice Combinations45611 / 48612
- Minimizing Coins39260 / 42518
- Coin Combinations I36113 / 39419
- Coin Combinations II30302 / 34804
- Removing Digits33503 / 34371
- Grid Paths31870 / 32949
- Book Shop28005 / 31338
- Array Description20237 / 22849
- Counting Towers11514 / 12223
- Edit Distance21002 / 22345
- Rectangle Cutting17525 / 19235
- Money Sums20902 / 21837
- Removal Game14933 / 16622
- Two Sets II16485 / 18004
- Increasing Subsequence16943 / 19262
- Projects11408 / 12961
- Elevator Rides6868 / 8846
- Counting Tilings3922 / 4318
- Counting Numbers5291 / 6042
Graph Algorithms
- Counting Rooms31167 / 33180
- Labyrinth20419 / 25393
- Building Roads26975 / 28133
- Message Route22923 / 24047
- Building Teams21989 / 23109
- Round Trip17070 / 18861
- Monsters10743 / 13244
- Shortest Routes I18288 / 20924
- Shortest Routes II15482 / 16982
- High Score7753 / 12756
- Flight Discount10794 / 13244
- Cycle Finding8028 / 10126
- Flight Routes7464 / 8423
- Round Trip II8955 / 10304
- Course Schedule12430 / 12985
- Longest Flight Route7665 / 10315
- Game Routes8985 / 9909
- Investigation6572 / 7151
- Planets Queries I5563 / 6806
- Planets Queries II2228 / 2773
- Planets Cycles3716 / 4184
- Road Reparation8900 / 9360
- Road Construction9387 / 9760
- Flight Routes Check7983 / 8826
- Planets and Kingdoms6431 / 6711
- Giant Pizza2591 / 2921
- Coin Collector4010 / 4552
- Mail Delivery3475 / 3872
- De Bruijn Sequence1869 / 1969
- Teleporters Path2752 / 3088
- Hamiltonian Flights3854 / 4389
- Knight's Tour1625 / 1927
- Download Speed2674 / 3803
- Police Chase2180 / 2506
- School Dance2401 / 2561
- Distinct Routes1535 / 2103
Range Queries
- Static Range Sum Queries21205 / 22200
- Static Range Minimum Queries15771 / 16893
- Dynamic Range Sum Queries16244 / 17016
- Dynamic Range Minimum Queries14773 / 15172
- Range Xor Queries14939 / 15167
- Range Update Queries11894 / 12825
- Forest Queries11679 / 12168
- Hotel Queries8517 / 9005
- List Removals7094 / 7499
- Salary Queries5243 / 6363
- Prefix Sum Queries4229 / 4631
- Pizzeria Queries3446 / 3578
- Subarray Sum Queries4400 / 4929
- Distinct Values Queries4122 / 5026
- Increasing Array Queries1489 / 1716
- Forest Queries II2838 / 3076
- Range Updates and Sums3397 / 4156
- Polynomial Queries2603 / 3061
- Range Queries and Copies1832 / 1987
Tree Algorithms
- Subordinates17529 / 18975
- Tree Matching9822 / 11595
- Tree Diameter14535 / 15585
- Tree Distances I10778 / 11704
- Tree Distances II8825 / 9224
- Company Queries I9744 / 10326
- Company Queries II9146 / 9668
- Distance Queries8541 / 9178
- Counting Paths5104 / 5474
- Subtree Queries6285 / 6740
- Path Queries5013 / 5310
- Path Queries II1770 / 2961
- Distinct Colors4779 / 5391
- Finding a Centroid3906 / 4089
- Fixed-Length Paths I1606 / 2321
- Fixed-Length Paths II666 / 1583
Mathematics
- Josephus Queries2546 / 3219
- Exponentiation14802 / 16005
- Exponentiation II10572 / 13033
- Counting Divisors12741 / 14606
- Common Divisors8552 / 10267
- Sum of Divisors4874 / 7478
- Divisor Analysis3164 / 4228
- Prime Multiples3437 / 4078
- Counting Coprime Pairs2167 / 2566
- Binomial Coefficients5979 / 6781
- Creating Strings II5021 / 5376
- Distributing Apples4905 / 5318
- Christmas Party3798 / 4132
- Bracket Sequences I2579 / 2862
- Bracket Sequences II1325 / 1530
- Counting Necklaces1285 / 1397
- Counting Grids1032 / 1104
- Fibonacci Numbers4377 / 5634
- Throwing Dice2370 / 2579
- Graph Paths I2163 / 2334
- Graph Paths II1814 / 1901
- Dice Probability2066 / 2195
- Moving Robots1036 / 1106
- Candy Lottery1592 / 1637
- Inversion Probability466 / 1430
- Stick Game2123 / 2183
- Nim Game I2678 / 2789
- Nim Game II2181 / 2280
- Stair Game1508 / 1654
- Grundy's Game964 / 1247
- Another Game1104 / 1204
String Algorithms
- Word Combinations3120 / 4796
- String Matching6235 / 8988
- Finding Borders4621 / 5178
- Finding Periods3156 / 3590
- Minimal Rotation1575 / 2580
- Longest Palindrome2376 / 3335
- Required Substring926 / 1509
- Palindrome Queries1146 / 1373
- Finding Patterns985 / 1459
- Counting Patterns888 / 1179
- Pattern Positions786 / 1008
- Distinct Substrings938 / 1131
- Repeating Substring957 / 1079
- String Functions909 / 960
- Substring Order I675 / 725
- Substring Order II443 / 562
- Substring Distribution614 / 672
Geometry
- Point Location Test4158 / 4793
- Line Segment Intersection2526 / 3296
- Polygon Area3026 / 3256
- Point in Polygon1662 / 2121
- Polygon Lattice Points1417 / 1473
- Minimum Euclidean Distance1292 / 1776
- Convex Hull2083 / 2534
Advanced Techniques
- Meet in the Middle3589 / 5546
- Hamming Distance1977 / 2143
- Beautiful Subgrids1393 / 1569
- Reachable Nodes1407 / 1528
- Reachability Queries967 / 1149
- Cut and Paste917 / 1032
- Substring Reversals802 / 882
- Reversals and Sums799 / 872
- Necessary Roads1208 / 1244
- Necessary Cities1128 / 1186
- Eulerian Subgraphs508 / 537
- Monster Game I732 / 805
- Monster Game II655 / 710
- Subarray Squares727 / 857
- Houses and Schools474 / 547
- Knuth Division556 / 629
- Apples and Bananas516 / 573
- One Bit Positions491 / 546
- Signal Processing459 / 502
- New Roads Queries1202 / 1466
- Dynamic Connectivity548 / 623
- Parcel Delivery439 / 500
- Task Assignment418 / 454
- Distinct Routes II349 / 407
Additional Problems
- Shortest Subsequence1988 / 2555
- Counting Bits2275 / 2946
- Swap Game1234 / 1592
- Prüfer Code874 / 969
- Acyclic Graph Edges1363 / 1455
- Strongly Connected Edges852 / 938
- Even Outdegree Edges777 / 907
- Multiplication Table2942 / 3358
- Advertisement2539 / 2709
- Special Substrings579 / 627
- Permutation Inversions623 / 689
- Maximum Xor Subarray1460 / 1599
- Movie Festival Queries644 / 721
- Chess Tournament726 / 831
- Tree Traversals699 / 785
- Network Renovation616 / 817
- Graph Girth1881 / 2197
- Intersection Points1150 / 1236
- Inverse Inversions632 / 663
- Monotone Subsequences429 / 476
- String Reorder510 / 563
- Stack Weights370 / 431
- Pyramid Array497 / 591
- Increasing Subsequence II1458 / 1582
- String Removals634 / 689
- Bit Inversions1479 / 1726
- Xor Pyramid778 / 989
- Writing Numbers509 / 550
- String Transform327 / 406
- Letter Pair Move Game116 / 171
- Maximum Building I1329 / 1393
- Sorting Methods531 / 568
- Cyclic Array662 / 762
- List of Sums299 / 401
- Increasing Array II498 / 567
- Food Division366 / 433
- Bit Problem963 / 1038
- 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 Artists314 / 403
- Course Schedule II1024 / 1456
- Removing Digits II127 / 269
- Coin Arrangement214 / 282
- Counting Bishops225 / 253
- Grid Puzzle I329 / 359
- Grid Puzzle II241 / 270
- Empty String923 / 1111
- 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 Company891 / 1137
- Flight Route Requests285 / 347
- Two Stacks Sorting94 / 324
- Tree Isomorphism II544 / 633
- Forbidden Cities454 / 594
- Area of Rectangles685 / 772
- Grid Completion132 / 174
- Creating Offices257 / 335
- Permutations II575 / 658
- Functional Graph Distribution146 / 183
- New Flight Routes202 / 485
- Grid Path Construction66 / 238