General
Introductory Problems
- Weird Algorithm176729 / 184595
- Missing Number152449 / 159344
- Repetitions132506 / 137482
- Increasing Array124915 / 129052
- Permutations109453 / 112604
- Number Spiral77778 / 84310
- Two Knights60002 / 61766
- Two Sets65237 / 69790
- Bit Strings74198 / 78079
- Trailing Zeros68705 / 72855
- Coin Piles61123 / 66483
- Palindrome Reorder56813 / 59762
- Gray Code38825 / 43292
- Tower of Hanoi36204 / 37583
- Creating Strings47930 / 49090
- Apple Division48650 / 54506
- Chessboard and Queens29606 / 30104
- Raab Game I7740 / 8673
- Mex Grid Construction7511 / 7873
- Knight Moves Grid7575 / 7741
- Grid Coloring I6368 / 6593
- Digit Queries20807 / 23836
- String Reorder5698 / 6503
- Grid Path Description11656 / 14921
Sorting and Searching
- Distinct Numbers87881 / 94543
- Apartments66070 / 72638
- Ferris Wheel63663 / 68183
- Concert Tickets51062 / 58861
- Restaurant Customers51963 / 55777
- Movie Festival50520 / 53251
- Sum of Two Values58377 / 64850
- Maximum Subarray Sum55714 / 57991
- Stick Lengths49925 / 52048
- Missing Coin Sum38229 / 39526
- Collecting Numbers39157 / 41675
- Collecting Numbers II17232 / 21436
- Playlist39084 / 44237
- Towers39059 / 41659
- Traffic Lights30418 / 33790
- Distinct Values Subarrays10508 / 11751
- Distinct Values Subsequences8100 / 8807
- Josephus Problem I23705 / 25894
- Josephus Problem II12909 / 17665
- Nested Ranges Check14137 / 15968
- Nested Ranges Count9457 / 11049
- Room Allocation23077 / 26248
- Factory Machines33462 / 36111
- Tasks and Deadlines26690 / 27207
- Reading Books21665 / 23108
- Sum of Three Values31182 / 34246
- Sum of Four Values19479 / 21483
- Nearest Smaller Values26114 / 26947
- Subarray Sums I34658 / 36731
- Subarray Sums II31615 / 37030
- Subarray Divisibility28602 / 30932
- Distinct Values Subarrays II17508 / 19024
- Array Division27103 / 28404
- Movie Festival II14729 / 17534
- Maximum Subarray Sum II13747 / 16190
Dynamic Programming
- Dice Combinations92370 / 97469
- Minimizing Coins79928 / 85527
- Coin Combinations I73049 / 78673
- Coin Combinations II61952 / 69563
- Removing Digits68864 / 70226
- Grid Paths I64694 / 66409
- Book Shop58345 / 63736
- Array Description43258 / 47670
- Counting Towers26962 / 28455
- Edit Distance43039 / 45257
- Longest Common Subsequence15096 / 15593
- Rectangle Cutting35554 / 38622
- Minimal Grid Path7039 / 11639
- Money Sums41920 / 43395
- Removal Game26030 / 33541
- Two Sets II33120 / 35407
- Mountain Range4864 / 8304
- Increasing Subsequence33621 / 37539
- Projects23679 / 26232
- Elevator Rides15545 / 19219
- Counting Tilings9110 / 9845
- Counting Numbers13621 / 15060
- Increasing Subsequence II6112 / 7168
Graph Algorithms
- Counting Rooms64274 / 67261
- Labyrinth45685 / 53666
- Building Roads56300 / 58170
- Message Route48822 / 50584
- Building Teams46076 / 48300
- Round Trip36527 / 39488
- Monsters25960 / 29972
- Shortest Routes I40328 / 43964
- Shortest Routes II32592 / 36176
- High Score20938 / 28207
- Flight Discount26839 / 30806
- Cycle Finding18923 / 22600
- Flight Routes18453 / 20370
- Round Trip II20480 / 22718
- Course Schedule27037 / 28349
- Longest Flight Route19841 / 23853
- Game Routes21621 / 22941
- Investigation16408 / 17497
- Planets Queries I14225 / 16397
- Planets Queries II5165 / 6409
- Planets Cycles8591 / 9490
- Road Reparation21053 / 21867
- Road Construction22963 / 23650
- Flight Routes Check18239 / 19605
- Planets and Kingdoms14851 / 15461
- Giant Pizza6255 / 6825
- Coin Collector9864 / 10785
- Mail Delivery7862 / 8530
- De Bruijn Sequence4138 / 4323
- Teleporters Path6100 / 6856
- Hamiltonian Flights9304 / 10522
- Knight's Tour3480 / 4160
- Download Speed6055 / 7880
- Police Chase4846 / 5376
- School Dance5314 / 5599
- Distinct Routes3753 / 4803
Range Queries
- Static Range Sum Queries44987 / 46963
- Static Range Minimum Queries30893 / 33065
- Dynamic Range Sum Queries32149 / 33514
- Dynamic Range Minimum Queries29033 / 29705
- Range Xor Queries29640 / 30027
- Range Update Queries23981 / 25600
- Forest Queries24632 / 25467
- Hotel Queries17471 / 18435
- List Removals14527 / 15211
- Salary Queries11233 / 13882
- 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 Queries8222 / 9949
- Distinct Values Queries II1452 / 1648
- Increasing Array Queries3124 / 3552
- Movie Festival Queries1744 / 1917
- Forest Queries II5105 / 5460
- Range Updates and Sums7194 / 8409
- Polynomial Queries5277 / 6150
- Range Queries and Copies3720 / 3962
- Missing Coin Sum Queries880 / 1202
Tree Algorithms
- Subordinates36976 / 39445
- Tree Matching21398 / 24622
- Tree Diameter30261 / 31929
- Tree Distances I23516 / 25123
- Tree Distances II19159 / 19997
- Company Queries I21535 / 22584
- Company Queries II20140 / 21130
- Distance Queries18167 / 19387
- Counting Paths11484 / 12104
- Subtree Queries13487 / 14319
- Path Queries10869 / 11455
- Path Queries II4568 / 6675
- Distinct Colors10422 / 11388
- Finding a Centroid8483 / 8810
- Fixed-Length Paths I4244 / 5316
- Fixed-Length Paths II2085 / 3603
Mathematics
- Josephus Queries5875 / 7317
- Exponentiation28610 / 30428
- Exponentiation II19982 / 23685
- Counting Divisors26316 / 29601
- Common Divisors16918 / 19484
- Sum of Divisors9648 / 14069
- Divisor Analysis6622 / 8734
- Prime Multiples7692 / 8884
- Counting Coprime Pairs5088 / 5855
- Next Prime2722 / 3093
- Binomial Coefficients12315 / 13573
- Creating Strings II10192 / 10727
- Distributing Apples9742 / 10448
- Christmas Party8095 / 8622
- Permutation Order1303 / 1338
- Permutation Rounds1898 / 2090
- Bracket Sequences I5422 / 5876
- Bracket Sequences II2891 / 3282
- Counting Necklaces2620 / 2828
- 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 Robots1890 / 1990
- Candy Lottery1970 / 3634
- Inversion Probability590 / 2680
- Stick Game4154 / 4251
- Nim Game I5552 / 5754
- Nim Game II4397 / 4565
- Stair Game2972 / 3218
- Grundy's Game2081 / 2719
- Another Game2356 / 2529
String Algorithms
- Word Combinations7177 / 10146
- String Matching13647 / 17972
- Finding Borders10059 / 10936
- 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 Functions1989 / 2083
- Inverse Suffix Array379 / 433
- String Transform685 / 810
- Substring Order I1434 / 1582
- Substring Order II976 / 1244
- Substring Distribution1336 / 1443
Geometry
- Point Location Test8595 / 9527
- Line Segment Intersection5096 / 6324
- Polygon Area5847 / 6164
- Point in Polygon3280 / 4114
- Polygon Lattice Points2664 / 2847
- Minimum Euclidean Distance2360 / 3288
- Convex Hull3911 / 4632
- 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 Middle8304 / 11135
- 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 Queries2616 / 3138
- Dynamic Connectivity1196 / 1336
- Parcel Delivery949 / 1035
- Task Assignment1093 / 1179
- Distinct Routes II722 / 813
Sliding Window Problems
- Sliding Window Sum8009 / 8265
- Sliding Window Minimum6020 / 6852
- Sliding Window Xor5886 / 5962
- Sliding Window Or2644 / 4376
- Sliding Window Distinct Values4197 / 4890
- Sliding Window Mode3267 / 3458
- Sliding Window Mex3085 / 3244
- Sliding Window Median15282 / 17361
- Sliding Window Cost9977 / 11460
- Sliding Window Inversions1650 / 1745
- Sliding Window Advertisement320 / 503
Interactive Problems
- Hidden Integer2892 / 3013
- Hidden Permutation1300 / 1504
- K-th Highest Score594 / 716
- Permuted Binary Strings694 / 713
- Colored Chairs654 / 693
- Inversion Sorting383 / 431
Bitwise Operations
- Counting Bits6221 / 7984
- Maximum Xor Subarray3674 / 4198
- Maximum Xor Subset1379 / 1513
- 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 / 1225
- Prüfer Code1725 / 1848
- Tree Traversals1419 / 1552
- Course Schedule II2349 / 3288
- Acyclic Graph Edges2455 / 2602
- Strongly Connected Edges1791 / 2079
- Even Outdegree Edges1579 / 1832
- Graph Girth3975 / 4480
- Fixed Length Walk Queries476 / 527
- Transfer Speeds Sum537 / 554
- 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 Cities765 / 1000
- Graph Coloring294 / 343
- Bus Companies340 / 350
- Split into Two Paths139 / 235
- Network Renovation1036 / 1359
- Forbidden Cities976 / 1260
- Creating Offices475 / 617
- New Flight Routes410 / 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 Distribution279 / 342
Additional Problems I
- Shortest Subsequence3270 / 4271
- Distinct Values Sum865 / 889
- Distinct Values Splits609 / 653
- Swap Game2259 / 2884
- Beautiful Permutation II753 / 1159
- Multiplication Table7811 / 8663
- Bubble Sort Rounds I553 / 624
- Bubble Sort Rounds II381 / 423
- Nearest Campsites I238 / 278
- Nearest Campsites II231 / 249
- Advertisement4911 / 5193
- Special Substrings1086 / 1188
- Counting LCM Arrays370 / 402
- Square Subsets285 / 314
- Subarray Sum Constraints579 / 616
- Water Containers Moves228 / 242
- Water Containers Queries263 / 278
- Stack Weights651 / 778
- Maximum Average Subarrays227 / 248
- Subsets with Fixed Average267 / 290
- Two Array Average273 / 304
- Pyramid Array861 / 1036
- Permutation Subsequence315 / 326
- Bit Inversions2564 / 2884
- Writing Numbers809 / 876
- Letter Pair Move Game235 / 325
- Maximum Building I2277 / 2377
- Sorting Methods842 / 899
- Cyclic Array1371 / 1545
- 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 II489 / 601
- Stick Divisions4151 / 4836
- Stick Difference105 / 335
- Coding Company1656 / 2163
- Two Stacks Sorting209 / 642