General
Introductory Problems
- Weird Algorithm176703 / 184567
- Missing Number152439 / 159333
- Repetitions132493 / 137471
- Increasing Array124903 / 129039
- Permutations109439 / 112590
- Number Spiral77768 / 84301
- Two Knights59996 / 61760
- Two Sets65232 / 69784
- Bit Strings74193 / 78075
- Trailing Zeros68697 / 72847
- Coin Piles61114 / 66471
- Palindrome Reorder56805 / 59753
- Gray Code38818 / 43284
- Tower of Hanoi36198 / 37577
- Creating Strings47927 / 49087
- Apple Division48645 / 54502
- Chessboard and Queens29599 / 30097
- Raab Game I7735 / 8668
- Mex Grid Construction7507 / 7869
- Knight Moves Grid7571 / 7736
- Grid Coloring I6365 / 6589
- Digit Queries20802 / 23830
- String Reorder5694 / 6499
- Grid Path Description11654 / 14918
Sorting and Searching
- Distinct Numbers87875 / 94537
- Apartments66061 / 72629
- Ferris Wheel63656 / 68174
- Concert Tickets51056 / 58854
- Restaurant Customers51958 / 55769
- Movie Festival50514 / 53244
- Sum of Two Values58370 / 64845
- Maximum Subarray Sum55709 / 57984
- Stick Lengths49924 / 52047
- Missing Coin Sum38223 / 39521
- Collecting Numbers39153 / 41671
- Collecting Numbers II17230 / 21432
- Playlist39084 / 44236
- Towers39057 / 41658
- Traffic Lights30416 / 33788
- Distinct Values Subarrays10504 / 11747
- Distinct Values Subsequences8098 / 8804
- Josephus Problem I23700 / 25889
- Josephus Problem II12907 / 17662
- Nested Ranges Check14137 / 15968
- Nested Ranges Count9456 / 11046
- Room Allocation23072 / 26245
- Factory Machines33461 / 36110
- Tasks and Deadlines26688 / 27205
- Reading Books21662 / 23104
- Sum of Three Values31181 / 34245
- Sum of Four Values19476 / 21480
- Nearest Smaller Values26110 / 26943
- Subarray Sums I34655 / 36728
- Subarray Sums II31613 / 37029
- Subarray Divisibility28602 / 30932
- Distinct Values Subarrays II17507 / 19023
- Array Division27100 / 28402
- Movie Festival II14728 / 17532
- Maximum Subarray Sum II13746 / 16188
Dynamic Programming
- Dice Combinations92360 / 97460
- Minimizing Coins79915 / 85512
- Coin Combinations I73041 / 78663
- Coin Combinations II61944 / 69555
- Removing Digits68853 / 70217
- Grid Paths I64648 / 66341
- Book Shop58336 / 63724
- Array Description43255 / 47664
- Counting Towers26961 / 28454
- Edit Distance43037 / 45254
- Longest Common Subsequence15092 / 15589
- Rectangle Cutting35552 / 38617
- Minimal Grid Path7039 / 11637
- Money Sums41918 / 43393
- Removal Game26027 / 33537
- Two Sets II33116 / 35404
- Mountain Range4863 / 8303
- Increasing Subsequence33617 / 37533
- Projects23677 / 26229
- Elevator Rides15544 / 19218
- Counting Tilings9109 / 9844
- Counting Numbers13617 / 15056
- Increasing Subsequence II6111 / 7167
Graph Algorithms
- Counting Rooms64272 / 67258
- Labyrinth45680 / 53661
- Building Roads56292 / 58162
- Message Route48816 / 50579
- Building Teams46072 / 48295
- Round Trip36523 / 39483
- Monsters25956 / 29968
- Shortest Routes I40325 / 43961
- Shortest Routes II32587 / 36171
- High Score20935 / 28205
- Flight Discount26833 / 30801
- Cycle Finding18921 / 22597
- Flight Routes18452 / 20367
- Round Trip II20480 / 22717
- Course Schedule27036 / 28348
- Longest Flight Route19837 / 23851
- Game Routes21619 / 22939
- Investigation16406 / 17496
- Planets Queries I14223 / 16395
- Planets Queries II5164 / 6407
- Planets Cycles8590 / 9489
- Road Reparation21051 / 21864
- Road Construction22959 / 23646
- Flight Routes Check18237 / 19602
- Planets and Kingdoms14851 / 15461
- Giant Pizza6255 / 6825
- Coin Collector9862 / 10783
- Mail Delivery7862 / 8530
- De Bruijn Sequence4138 / 4323
- Teleporters Path6100 / 6856
- Hamiltonian Flights9304 / 10522
- Knight's Tour3480 / 4160
- Download Speed6055 / 7880
- Police Chase4845 / 5375
- School Dance5314 / 5598
- Distinct Routes3752 / 4802
Range Queries
- Static Range Sum Queries44980 / 46956
- Static Range Minimum Queries30889 / 33061
- Dynamic Range Sum Queries32142 / 33506
- Dynamic Range Minimum Queries29028 / 29700
- Range Xor Queries29635 / 30022
- Range Update Queries23979 / 25598
- Forest Queries24627 / 25462
- Hotel Queries17468 / 18432
- List Removals14525 / 15209
- Salary Queries11229 / 13879
- Prefix Sum Queries9408 / 10106
- Pizzeria Queries7513 / 7768
- Visible Buildings Queries2298 / 2496
- Range Interval Queries1754 / 2327
- Subarray Sum Queries8673 / 9353
- Subarray Sum Queries II2589 / 2667
- Distinct Values Queries8221 / 9947
- Distinct Values Queries II1452 / 1648
- Increasing Array Queries3124 / 3552
- Movie Festival Queries1744 / 1917
- Forest Queries II5105 / 5460
- Range Updates and Sums7193 / 8408
- Polynomial Queries5277 / 6150
- Range Queries and Copies3720 / 3962
- Missing Coin Sum Queries880 / 1202
Tree Algorithms
- Subordinates36974 / 39443
- Tree Matching21397 / 24621
- Tree Diameter30258 / 31926
- Tree Distances I23516 / 25123
- Tree Distances II19155 / 19993
- Company Queries I21531 / 22579
- Company Queries II20134 / 21124
- Distance Queries18163 / 19383
- Counting Paths11482 / 12102
- Subtree Queries13486 / 14318
- Path Queries10869 / 11455
- Path Queries II4567 / 6674
- Distinct Colors10421 / 11385
- Finding a Centroid8483 / 8810
- Fixed-Length Paths I4244 / 5316
- Fixed-Length Paths II2085 / 3603
Mathematics
- Josephus Queries5875 / 7317
- Exponentiation28609 / 30427
- Exponentiation II19980 / 23683
- Counting Divisors26314 / 29598
- Common Divisors16918 / 19484
- Sum of Divisors9647 / 14068
- Divisor Analysis6621 / 8734
- Prime Multiples7690 / 8882
- Counting Coprime Pairs5087 / 5855
- Next Prime2720 / 3091
- Binomial Coefficients12314 / 13573
- Creating Strings II10192 / 10727
- Distributing Apples9741 / 10447
- Christmas Party8093 / 8621
- Permutation Order1303 / 1338
- Permutation Rounds1898 / 2089
- Bracket Sequences I5421 / 5875
- Bracket Sequences II2891 / 3282
- Counting Necklaces2619 / 2827
- Counting Grids2205 / 2339
- Fibonacci Numbers8049 / 10002
- Throwing Dice4253 / 4601
- Graph Paths I4127 / 4395
- Graph Paths II3459 / 3619
- System of Linear Equations658 / 713
- Sum of Four Squares937 / 1122
- Triangle Number Sums822 / 982
- Dice Probability3645 / 3912
- Moving Robots1889 / 1989
- Candy Lottery1969 / 3633
- Inversion Probability590 / 2680
- Stick Game4154 / 4251
- Nim Game I5551 / 5753
- Nim Game II4396 / 4564
- Stair Game2971 / 3217
- Grundy's Game2080 / 2718
- Another Game2355 / 2528
String Algorithms
- Word Combinations7175 / 10143
- String Matching13647 / 17972
- Finding Borders10058 / 10935
- Finding Periods7193 / 8087
- Minimal Rotation3592 / 5235
- Longest Palindrome5284 / 6841
- All Palindromes968 / 1083
- Required Substring2018 / 2985
- Palindrome Queries2466 / 2841
- Finding Patterns2342 / 3234
- Counting Patterns2224 / 2705
- Pattern Positions1878 / 2251
- Distinct Substrings2100 / 2484
- Distinct Subsequences1351 / 1428
- Repeating Substring2269 / 2597
- String Functions1988 / 2082
- Inverse Suffix Array378 / 432
- String Transform685 / 810
- Substring Order I1433 / 1581
- Substring Order II976 / 1243
- Substring Distribution1335 / 1442
Geometry
- Point Location Test8595 / 9527
- Line Segment Intersection5096 / 6324
- Polygon Area5846 / 6163
- Point in Polygon3279 / 4113
- Polygon Lattice Points2663 / 2846
- Minimum Euclidean Distance2359 / 3288
- Convex Hull3911 / 4631
- Maximum Manhattan Distances849 / 882
- All Manhattan Distances888 / 973
- Intersection Points2322 / 2499
- Line Segments Trace I464 / 479
- Line Segments Trace II386 / 405
- Lines and Queries I507 / 532
- Lines and Queries II453 / 474
- Area of Rectangles1370 / 1523
- Robot Path374 / 680
Advanced Techniques
- Meet in the Middle8303 / 11133
- Hamming Distance3663 / 4002
- Corner Subgrid Check324 / 698
- Corner Subgrid Count2498 / 2838
- Reachable Nodes2604 / 2788
- Reachability Queries1745 / 2041
- Cut and Paste1799 / 1986
- Substring Reversals1588 / 1713
- Reversals and Sums1615 / 1724
- Necessary Roads2324 / 2383
- Necessary Cities2158 / 2252
- Eulerian Subgraphs923 / 972
- Monster Game I1381 / 1528
- Monster Game II1219 / 1300
- Subarray Squares1726 / 1999
- Houses and Schools939 / 1110
- Knuth Division1125 / 1260
- Apples and Bananas1313 / 1418
- One Bit Positions992 / 1078
- Signal Processing977 / 1042
- New Roads Queries2615 / 3138
- Dynamic Connectivity1196 / 1336
- Parcel Delivery949 / 1035
- Task Assignment1093 / 1179
- Distinct Routes II721 / 812
Sliding Window Problems
- Sliding Window Sum8008 / 8264
- Sliding Window Minimum6018 / 6851
- Sliding Window Xor5886 / 5962
- Sliding Window Or2644 / 4376
- Sliding Window Distinct Values4197 / 4890
- Sliding Window Mode3267 / 3458
- Sliding Window Mex3085 / 3244
- Sliding Window Median15281 / 17360
- Sliding Window Cost9977 / 11460
- Sliding Window Inversions1650 / 1745
- Sliding Window Advertisement320 / 503
Interactive Problems
- Hidden Integer2891 / 3012
- Hidden Permutation1300 / 1504
- K-th Highest Score594 / 716
- Permuted Binary Strings694 / 713
- Colored Chairs653 / 692
- Inversion Sorting382 / 430
Bitwise Operations
- Counting Bits6221 / 7983
- Maximum Xor Subarray3674 / 4197
- Maximum Xor Subset1378 / 1512
- Number of Subset Xors1199 / 1226
- K Subset Xors629 / 737
- All Subarray Xors379 / 583
- Xor Pyramid Peak2444 / 2925
- Xor Pyramid Diagonal432 / 483
- Xor Pyramid Row372 / 435
- SOS Bit Problem2584 / 2736
- And Subset Count613 / 636
Construction Problems
- Inverse Inversions2062 / 2201
- Monotone Subsequences1250 / 1476
- Third Permutation554 / 682
- Permutation Prime Sums559 / 599
- Chess Tournament1388 / 1597
- Distinct Sums Grid197 / 295
- Filling Trominos308 / 530
- Grid Path Construction170 / 498
Advanced Graph Problems
- Nearest Shops951 / 1223
- Prüfer Code1725 / 1848
- Tree Traversals1419 / 1552
- Course Schedule II2349 / 3288
- Acyclic Graph Edges2454 / 2601
- Strongly Connected Edges1791 / 2079
- Even Outdegree Edges1579 / 1832
- Graph Girth3975 / 4480
- Fixed Length Walk Queries476 / 527
- Transfer Speeds Sum536 / 553
- MST Edge Check880 / 951
- MST Edge Set Check325 / 367
- MST Edge Cost520 / 541
- Network Breakdown1342 / 1457
- Tree Coin Collecting I456 / 495
- Tree Coin Collecting II259 / 296
- Tree Isomorphism I1229 / 1452
- Tree Isomorphism II1022 / 1168
- Flight Route Requests581 / 718
- Critical Cities503 / 751
- Visiting Cities764 / 1000
- Graph Coloring294 / 343
- Bus Companies340 / 350
- Split into Two Paths139 / 235
- Network Renovation1036 / 1359
- Forbidden Cities976 / 1260
- Creating Offices475 / 617
- New Flight Routes409 / 1039
Counting Problems
- Filled Subgrid Count I784 / 872
- Filled Subgrid Count II418 / 516
- All Letter Subgrid Count I239 / 343
- All Letter Subgrid Count II150 / 227
- Border Subgrid Count I128 / 218
- Border Subgrid Count II141 / 163
- Raab Game II145 / 165
- Empty String1917 / 2324
- Permutation Inversions1140 / 1255
- Counting Bishops445 / 498
- Counting Sequences765 / 820
- Grid Paths II849 / 1068
- Counting Permutations982 / 1107
- Grid Completion260 / 329
- Counting Reorders297 / 412
- Tournament Graph Distribution145 / 155
- Collecting Numbers Distribution153 / 160
- Functional Graph Distribution278 / 342
Additional Problems I
- Shortest Subsequence3269 / 4270
- Distinct Values Sum865 / 889
- Distinct Values Splits609 / 653
- Swap Game2257 / 2882
- Beautiful Permutation II753 / 1159
- Multiplication Table7809 / 8661
- Bubble Sort Rounds I552 / 623
- Bubble Sort Rounds II381 / 423
- Nearest Campsites I237 / 277
- Nearest Campsites II230 / 248
- Advertisement4910 / 5191
- Special Substrings1085 / 1187
- Counting LCM Arrays369 / 401
- Square Subsets284 / 313
- Subarray Sum Constraints579 / 616
- Water Containers Moves228 / 242
- Water Containers Queries262 / 277
- Stack Weights650 / 777
- Maximum Average Subarrays227 / 248
- Subsets with Fixed Average267 / 290
- Two Array Average272 / 304
- Pyramid Array860 / 1035
- Permutation Subsequence315 / 326
- Bit Inversions2563 / 2883
- Writing Numbers808 / 875
- Letter Pair Move Game235 / 325
- Maximum Building I2276 / 2376
- Sorting Methods842 / 899
- Cyclic Array1370 / 1544
- List of Sums543 / 702
Additional Problems II
- Bouncing Ball Steps316 / 348
- Bouncing Ball Cycle133 / 180
- Knight Moves Queries161 / 193
- K Subset Sums I257 / 320
- K Subset Sums II154 / 193
- Increasing Array II903 / 1031
- Food Division578 / 688
- Swap Round Sorting447 / 553
- Binary Subsequences320 / 461
- School Excursion1532 / 1618
- Coin Grid1019 / 1184
- Grid Coloring II171 / 220
- Programmers and Artists562 / 779
- Removing Digits II244 / 518
- Coin Arrangement371 / 491
- Replace with Difference171 / 204
- Grid Puzzle I605 / 663
- Grid Puzzle II588 / 643
- Bit Substrings446 / 538
- Reversal Sorting393 / 473
- Book Shop II1425 / 1622
- GCD Subsets510 / 526
- Minimum Cost Pairs179 / 225
- Same Sum Subsets157 / 297
- Mex Grid Queries927 / 1082
- Maximum Building II488 / 600
- Stick Divisions4150 / 4835
- Stick Difference105 / 335
- Coding Company1656 / 2163
- Two Stacks Sorting209 / 642