General
Introductory Problems
- Weird Algorithm130611 / 136828
- Missing Number112324 / 118080
- Repetitions97914 / 102164
- Increasing Array91882 / 95443
- Permutations80627 / 83240
- Number Spiral57048 / 62326
- Two Knights43268 / 44721
- Two Sets46932 / 50777
- Bit Strings54129 / 57217
- Trailing Zeros50577 / 53956
- Coin Piles44705 / 49153
- Palindrome Reorder41372 / 43795
- Gray Code27008 / 30612
- Tower of Hanoi25058 / 26096
- Creating Strings35221 / 36210
- Apple Division34919 / 39697
- Chessboard and Queens20877 / 21290
- Raab Game I421 / 476
- Mex Grid Construction434 / 460
- Knight Moves Grid417 / 424
- Grid Coloring I301 / 311
- Digit Queries14871 / 17596
- String Reorder789 / 895
- Grid Paths8413 / 10980
Sorting and Searching
- Distinct Numbers63379 / 68802
- Apartments46504 / 52083
- Ferris Wheel44503 / 48255
- Concert Tickets35882 / 42188
- Restaurant Customers36676 / 39768
- Movie Festival34754 / 36961
- Sum of Two Values40948 / 46276
- Maximum Subarray Sum39900 / 41781
- Stick Lengths35564 / 37358
- Missing Coin Sum26135 / 27151
- Collecting Numbers26805 / 28893
- Collecting Numbers II10799 / 14073
- Playlist26982 / 31167
- Towers27566 / 29674
- Traffic Lights21275 / 23993
- Distinct Values Subarrays593 / 627
- Distinct Values Subsequences407 / 442
- Josephus Problem I15933 / 17762
- Josephus Problem II8677 / 11891
- Nested Ranges Check8944 / 10434
- Nested Ranges Count6171 / 7296
- Room Allocation15827 / 18347
- Factory Machines22330 / 24593
- Tasks and Deadlines18340 / 18757
- Reading Books14730 / 15821
- Sum of Three Values21734 / 24300
- Sum of Four Values13499 / 15177
- Nearest Smaller Values18083 / 18739
- Subarray Sums I23653 / 25421
- Subarray Sums II21149 / 25556
- Subarray Divisibility19667 / 21614
- Distinct Values Subarrays II11329 / 12748
- Array Division18603 / 19658
- Movie Festival II9789 / 11992
- Maximum Subarray Sum II8986 / 10828
Dynamic Programming
- Dice Combinations64488 / 68496
- Minimizing Coins55580 / 59950
- Coin Combinations I50761 / 55207
- Coin Combinations II42731 / 48782
- Removing Digits47470 / 48534
- Grid Paths44920 / 46325
- Book Shop39759 / 44107
- Array Description28933 / 32459
- Counting Towers17203 / 18266
- Edit Distance29500 / 31275
- Longest Common Subsequence590 / 616
- Rectangle Cutting24501 / 26855
- Minimal Grid Path257 / 395
- Money Sums29415 / 30634
- Removal Game16147 / 23448
- Two Sets II23093 / 25075
- Mountain Range240 / 370
- Increasing Subsequence23753 / 26842
- Projects16125 / 18206
- Elevator Rides10034 / 12818
- Counting Tilings5808 / 6392
- Counting Numbers7828 / 8970
- Increasing Subsequence II2122 / 2284
Graph Algorithms
- Counting Rooms44143 / 46637
- Labyrinth29794 / 36483
- Building Roads38383 / 39888
- Message Route32634 / 34094
- Building Teams30808 / 32751
- Round Trip24278 / 26700
- Monsters15969 / 19322
- Shortest Routes I26400 / 29592
- Shortest Routes II21328 / 24264
- High Score12136 / 18312
- Flight Discount16344 / 19547
- Cycle Finding11542 / 14569
- Flight Routes11141 / 12513
- Round Trip II13016 / 14827
- Course Schedule17362 / 18549
- Longest Flight Route11592 / 14945
- Game Routes13281 / 14417
- Investigation9781 / 10594
- Planets Queries I8509 / 10128
- Planets Queries II3095 / 3918
- Planets Cycles5312 / 5983
- Road Reparation13175 / 13780
- Road Construction14392 / 14914
- Flight Routes Check11780 / 12882
- Planets and Kingdoms9358 / 9725
- Giant Pizza3866 / 4298
- Coin Collector5976 / 6722
- Mail Delivery5097 / 5624
- De Bruijn Sequence2687 / 2820
- Teleporters Path3819 / 4473
- Hamiltonian Flights5788 / 6614
- Knight's Tour2176 / 2677
- Download Speed4071 / 5399
- Police Chase3131 / 3544
- School Dance3460 / 3687
- Distinct Routes2323 / 3109
Range Queries
- Static Range Sum Queries30502 / 31882
- Static Range Minimum Queries21708 / 23290
- Dynamic Range Sum Queries22487 / 23502
- Dynamic Range Minimum Queries20540 / 21049
- Range Xor Queries21238 / 21544
- Range Update Queries16684 / 17989
- Forest Queries16807 / 17454
- Hotel Queries11933 / 12770
- List Removals9957 / 10549
- Salary Queries7201 / 9298
- Prefix Sum Queries6205 / 6781
- Pizzeria Queries4993 / 5207
- Visible Buildings Queries182 / 187
- Range Interval Queries133 / 160
- Subarray Sum Queries6269 / 6865
- Subarray Sum Queries II154 / 162
- Distinct Values Queries5573 / 7064
- Distinct Values Queries II109 / 123
- Increasing Array Queries2170 / 2507
- Movie Festival Queries857 / 962
- Forest Queries II3806 / 4119
- Range Updates and Sums4909 / 5930
- Polynomial Queries3648 / 4309
- Range Queries and Copies2585 / 2791
- Missing Coin Sum Queries346 / 480
Tree Algorithms
- Subordinates25173 / 27040
- Tree Matching14027 / 16498
- Tree Diameter20563 / 21910
- Tree Distances I15369 / 16622
- Tree Distances II12635 / 13193
- Company Queries I13957 / 14753
- Company Queries II13081 / 13764
- Distance Queries11968 / 12894
- Counting Paths7316 / 7822
- Subtree Queries9031 / 9663
- Path Queries7210 / 7652
- Path Queries II2821 / 4367
- Distinct Colors6888 / 7675
- Finding a Centroid5629 / 5870
- Fixed-Length Paths I2606 / 3466
- Fixed-Length Paths II1171 / 2308
Mathematics
- Josephus Queries3829 / 4811
- Exponentiation20427 / 21918
- Exponentiation II14585 / 17669
- Counting Divisors18498 / 21019
- Common Divisors12198 / 14327
- Sum of Divisors6821 / 10293
- Divisor Analysis4538 / 6116
- Prime Multiples5104 / 6052
- Counting Coprime Pairs3304 / 3906
- Next Prime227 / 240
- Binomial Coefficients8455 / 9477
- Creating Strings II7206 / 7662
- Distributing Apples6970 / 7536
- Christmas Party5410 / 5856
- Permutation Order93 / 95
- Permutation Rounds110 / 116
- Bracket Sequences I3787 / 4163
- Bracket Sequences II1959 / 2265
- Counting Necklaces1795 / 1964
- Counting Grids1448 / 1560
- Fibonacci Numbers5995 / 7606
- Throwing Dice3123 / 3409
- Graph Paths I2936 / 3159
- Graph Paths II2447 / 2565
- System of Linear Equations54 / 57
- Sum of Four Squares89 / 104
- Triangle Number Sums62 / 84
- Dice Probability2684 / 2899
- Moving Robots1367 / 1456
- Candy Lottery1190 / 2444
- Inversion Probability282 / 1926
- Stick Game2991 / 3063
- Nim Game I3970 / 4129
- Nim Game II3173 / 3314
- Stair Game2131 / 2330
- Grundy's Game1425 / 1873
- Another Game1631 / 1769
String Algorithms
- Word Combinations4751 / 7064
- String Matching9459 / 12956
- Finding Borders6897 / 7603
- Finding Periods4882 / 5563
- Minimal Rotation2345 / 3708
- Longest Palindrome3612 / 4857
- All Palindromes67 / 70
- Required Substring1342 / 2133
- Palindrome Queries1726 / 2030
- Finding Patterns1533 / 2226
- Counting Patterns1451 / 1829
- Pattern Positions1226 / 1526
- Distinct Substrings1417 / 1703
- Distinct Subsequences827 / 890
- Repeating Substring1585 / 1781
- String Functions1368 / 1437
- Inverse Suffix Array31 / 35
- String Transform408 / 510
- Substring Order I972 / 1106
- Substring Order II643 / 830
- Substring Distribution903 / 987
Geometry
- Point Location Test6070 / 6832
- Line Segment Intersection3614 / 4627
- Polygon Area4258 / 4537
- Point in Polygon2275 / 2962
- Polygon Lattice Points1966 / 2042
- Minimum Euclidean Distance1703 / 2432
- Convex Hull2871 / 3459
- Maximum Manhattan Distances63 / 65
- All Manhattan Distances75 / 80
- Intersection Points1578 / 1706
- Line Segments Trace I37 / 38
- Line Segments Trace II28 / 29
- Lines and Queries I43 / 46
- Lines and Queries II34 / 37
- Area of Rectangles915 / 1031
- Robot Path245 / 437
Advanced Techniques
- Meet in the Middle5521 / 7959
- Hamming Distance2795 / 3042
- Corner Subgrid Check55 / 71
- Corner Subgrid Count1989 / 2225
- Reachable Nodes1966 / 2129
- Reachability Queries1324 / 1574
- Cut and Paste1288 / 1443
- Substring Reversals1127 / 1238
- Reversals and Sums1134 / 1232
- Necessary Roads1652 / 1695
- Necessary Cities1538 / 1616
- Eulerian Subgraphs684 / 724
- Monster Game I996 / 1106
- Monster Game II878 / 952
- Subarray Squares1118 / 1348
- Houses and Schools631 / 758
- Knuth Division749 / 858
- Apples and Bananas797 / 878
- One Bit Positions675 / 750
- Signal Processing628 / 683
- New Roads Queries1790 / 2189
- Dynamic Connectivity823 / 935
- Parcel Delivery610 / 690
- Task Assignment696 / 745
- Distinct Routes II473 / 549
Sliding Window Problems
- Sliding Window Sum436 / 448
- Sliding Window Minimum299 / 358
- Sliding Window Xor369 / 380
- Sliding Window Or140 / 277
- Sliding Window Distinct Values291 / 295
- Sliding Window Mode222 / 226
- Sliding Window Mex205 / 208
- Sliding Window Median12056 / 13807
- Sliding Window Cost8062 / 9316
- Sliding Window Inversions149 / 158
- Sliding Window Advertisement22 / 29
Interactive Problems
- Hidden Integer277 / 286
- Hidden Permutation123 / 151
- K-th Highest Score42 / 47
- Permuted Binary Strings70 / 71
- Colored Chairs64 / 66
- Inversion Sorting40 / 44
Bitwise Operations
- Counting Bits3101 / 3936
- Maximum Xor Subarray1981 / 2179
- Maximum Xor Subset90 / 97
- Number of Subset Xors85 / 86
- K Subset Xors44 / 47
- All Subarray Xors40 / 48
- Xor Pyramid Peak1430 / 1796
- Xor Pyramid Diagonal43 / 48
- Xor Pyramid Row34 / 36
- SOS Bit Problem1487 / 1596
- And Subset Count39 / 39
Construction Problems
- Inverse Inversions926 / 979
- Monotone Subsequences597 / 688
- Third Permutation42 / 44
- Permutation Prime Sums48 / 50
- Chess Tournament934 / 1084
- Distinct Sums Grid12 / 17
- Filling Trominos191 / 316
- Grid Path Construction97 / 384
Advanced Graph Problems
- Nearest Shops64 / 73
- Prüfer Code1202 / 1314
- Tree Traversals916 / 1024
- Course Schedule II1409 / 2008
- Acyclic Graph Edges1825 / 1940
- Strongly Connected Edges1217 / 1356
- Even Outdegree Edges1101 / 1293
- Graph Girth2687 / 3101
- Fixed Length Walk Queries38 / 39
- Transfer Speeds Sum51 / 51
- MST Edge Check44 / 46
- MST Edge Set Check23 / 23
- MST Edge Cost33 / 34
- Network Breakdown781 / 830
- Tree Coin Collecting I35 / 37
- Tree Coin Collecting II14 / 15
- Tree Isomorphism I924 / 1068
- Tree Isomorphism II728 / 838
- Flight Route Requests377 / 458
- Critical Cities336 / 516
- Visiting Cities565 / 747
- Graph Coloring25 / 27
- Bus Companies28 / 29
- Split into Two Paths13 / 17
- Network Renovation811 / 1075
- Forbidden Cities651 / 861
- Creating Offices344 / 447
- New Flight Routes269 / 671
Counting Problems
- Filled Subgrid Count I45 / 47
- Filled Subgrid Count II17 / 21
- All Letter Subgrid Count I11 / 18
- All Letter Subgrid Count II9 / 10
- Border Subgrid Count I7 / 19
- Border Subgrid Count II9 / 12
- Raab Game II9 / 10
- Empty String1294 / 1572
- Permutation Inversions856 / 941
- Counting Bishops301 / 341
- Counting Sequences517 / 559
- Grid Paths625 / 782
- Counting Permutations742 / 844
- Grid Completion168 / 221
- Counting Reorders170 / 259
- Tournament Graph Distribution11 / 11
- Collecting Numbers Distribution15 / 15
- Functional Graph Distribution192 / 241
Additional Problems I
- Shortest Subsequence2582 / 3441
- Distinct Values Sum68 / 73
- Distinct Values Splits51 / 52
- Swap Game1750 / 2231
- Beautiful Permutation II25 / 32
- Multiplication Table5275 / 5925
- Bubble Sort Rounds I24 / 28
- Bubble Sort Rounds II14 / 14
- Nearest Campsites I16 / 20
- Nearest Campsites II14 / 18
- Advertisement3604 / 3825
- Special Substrings838 / 920
- Counting LCM Arrays26 / 26
- Square Subsets26 / 26
- Subarray Sum Constraints20 / 21
- Water Containers Moves14 / 15
- Water Containers Queries18 / 19
- Stack Weights493 / 581
- Maximum Average Subarrays15 / 17
- Subsets with Fixed Average21 / 21
- Two Array Average23 / 24
- Pyramid Array615 / 745
- Permutation Subsequence24 / 25
- Bit Inversions1993 / 2290
- Writing Numbers642 / 698
- Letter Pair Move Game163 / 238
- Maximum Building I1789 / 1873
- Sorting Methods684 / 734
- Cyclic Array952 / 1087
- List of Sums389 / 519
Additional Problems II
- Bouncing Ball Steps20 / 20
- Bouncing Ball Cycle11 / 16
- Knight Moves Queries20 / 23
- K Subset Sums I20 / 22
- K Subset Sums II11 / 13
- Increasing Array II679 / 784
- Food Division456 / 542
- Swap Round Sorting359 / 444
- Binary Subsequences239 / 359
- School Excursion1145 / 1220
- Coin Grid686 / 819
- Grid Coloring II19 / 24
- Programmers and Artists429 / 561
- Removing Digits II174 / 391
- Coin Arrangement276 / 366
- Replace with Difference17 / 20
- Grid Puzzle I433 / 479
- Grid Puzzle II367 / 410
- Bit Substrings303 / 378
- Reversal Sorting294 / 361
- Book Shop II940 / 1092
- GCD Subsets54 / 57
- Minimum Cost Pairs15 / 18
- Same Sum Subsets17 / 24
- Mex Grid Queries709 / 847
- Maximum Building II362 / 450
- Stick Divisions3270 / 3865
- Stick Difference4 / 19
- Coding Company1209 / 1603
- Two Stacks Sorting138 / 423