General
Introductory Problems
- Weird Algorithm163775 / 171285
- Missing Number141366 / 148005
- Repetitions122949 / 127744
- Increasing Array115728 / 119719
- Permutations101611 / 104613
- Number Spiral71879 / 78169
- Two Knights55164 / 56861
- Two Sets60025 / 64424
- Bit Strings68607 / 72330
- Trailing Zeros63640 / 67606
- Coin Piles56474 / 61624
- Palindrome Reorder52505 / 55358
- Gray Code35493 / 39744
- Tower of Hanoi32968 / 34266
- Creating Strings44297 / 45413
- Apple Division44720 / 50371
- Chessboard and Queens27011 / 27489
- Raab Game I5784 / 6567
- Mex Grid Construction5636 / 5948
- Knight Moves Grid5672 / 5796
- Grid Coloring I4739 / 4903
- Digit Queries19038 / 22007
- String Reorder4297 / 4971
- Grid Path Description10573 / 13673
Sorting and Searching
- Distinct Numbers80979 / 87377
- Apartments60475 / 66853
- Ferris Wheel58017 / 62372
- Concert Tickets46539 / 53978
- Restaurant Customers47343 / 50993
- Movie Festival45791 / 48417
- Sum of Two Values53307 / 59498
- Maximum Subarray Sum51204 / 53417
- Stick Lengths45752 / 47800
- Missing Coin Sum34707 / 35946
- Collecting Numbers35549 / 37957
- Collecting Numbers II15126 / 19147
- Playlist35541 / 40466
- Towers35575 / 38060
- Traffic Lights27633 / 30840
- Distinct Values Subarrays7758 / 8956
- Distinct Values Subsequences5927 / 6536
- Josephus Problem I21251 / 23342
- Josephus Problem II11552 / 15880
- Nested Ranges Check12455 / 14225
- Nested Ranges Count8376 / 9849
- Room Allocation20811 / 23807
- Factory Machines30039 / 32612
- Tasks and Deadlines23990 / 24486
- Reading Books19411 / 20777
- Sum of Three Values28321 / 31283
- Sum of Four Values17619 / 19541
- Nearest Smaller Values23660 / 24460
- Subarray Sums I31397 / 33420
- Subarray Sums II28558 / 33738
- Subarray Divisibility25849 / 28092
- Distinct Values Subarrays II15676 / 17150
- Array Division24536 / 25784
- Movie Festival II13165 / 15837
- Maximum Subarray Sum II12237 / 14548
Dynamic Programming
- Dice Combinations84326 / 89139
- Minimizing Coins72887 / 78192
- Coin Combinations I66633 / 71987
- Coin Combinations II56388 / 63609
- Removing Digits62682 / 63932
- Grid Paths I58987 / 60624
- Book Shop52836 / 57962
- Array Description38920 / 43116
- Counting Towers23815 / 25219
- Edit Distance38964 / 41106
- Longest Common Subsequence11121 / 11528
- Rectangle Cutting32107 / 35008
- Minimal Grid Path4906 / 8642
- Money Sums37988 / 39407
- Removal Game22939 / 30318
- Two Sets II29872 / 32088
- Mountain Range3413 / 6129
- Increasing Subsequence30506 / 34221
- Projects21190 / 23627
- Elevator Rides13605 / 17029
- Counting Tilings7986 / 8685
- Counting Numbers11425 / 12798
- Increasing Subsequence II4998 / 5814
Graph Algorithms
- Counting Rooms58252 / 61125
- Labyrinth40609 / 48323
- Building Roads50768 / 52574
- Message Route43766 / 45469
- Building Teams41354 / 43526
- Round Trip32671 / 35504
- Monsters22684 / 26551
- Shortest Routes I36063 / 39620
- Shortest Routes II29119 / 32555
- High Score18012 / 25014
- Flight Discount23281 / 27091
- Cycle Finding16446 / 20008
- Flight Routes15963 / 17773
- Round Trip II17999 / 20156
- Course Schedule23981 / 25277
- Longest Flight Route17102 / 20976
- Game Routes18892 / 20170
- Investigation14090 / 15112
- Planets Queries I12206 / 14258
- Planets Queries II4442 / 5592
- Planets Cycles7471 / 8317
- Road Reparation18531 / 19299
- Road Construction20391 / 21039
- Flight Routes Check16157 / 17474
- Planets and Kingdoms13036 / 13555
- Giant Pizza5463 / 5995
- Coin Collector8554 / 9434
- Mail Delivery7013 / 7658
- De Bruijn Sequence3713 / 3885
- Teleporters Path5382 / 6118
- Hamiltonian Flights8130 / 9247
- Knight's Tour3086 / 3725
- Download Speed5393 / 7153
- Police Chase4308 / 4817
- School Dance4735 / 5000
- Distinct Routes3338 / 4341
Range Queries
- Static Range Sum Queries40763 / 42583
- Static Range Minimum Queries28254 / 30246
- Dynamic Range Sum Queries29333 / 30615
- Dynamic Range Minimum Queries26541 / 27171
- Range Xor Queries27324 / 27697
- Range Update Queries21817 / 23359
- Forest Queries22359 / 23157
- Hotel Queries15846 / 16776
- List Removals13152 / 13810
- Salary Queries9982 / 12500
- Prefix Sum Queries8487 / 9157
- Pizzeria Queries6820 / 7065
- Visible Buildings Queries1810 / 1974
- Range Interval Queries1394 / 1874
- Subarray Sum Queries7966 / 8619
- Subarray Sum Queries II2017 / 2086
- Distinct Values Queries7498 / 9168
- Distinct Values Queries II1170 / 1328
- Increasing Array Queries2884 / 3294
- Movie Festival Queries1536 / 1701
- Forest Queries II4749 / 5098
- Range Updates and Sums6502 / 7675
- Polynomial Queries4809 / 5644
- Range Queries and Copies3414 / 3644
- Missing Coin Sum Queries793 / 1033
Tree Algorithms
- Subordinates33294 / 35619
- Tree Matching18974 / 21988
- Tree Diameter27170 / 28774
- Tree Distances I20839 / 22376
- Tree Distances II16998 / 17783
- Company Queries I18966 / 19956
- Company Queries II17744 / 18672
- Distance Queries16048 / 17209
- Counting Paths10089 / 10675
- Subtree Queries12101 / 12879
- Path Queries9736 / 10298
- Path Queries II4069 / 6044
- Distinct Colors9384 / 10316
- Finding a Centroid7578 / 7882
- Fixed-Length Paths I3733 / 4755
- Fixed-Length Paths II1775 / 3182
Mathematics
- Josephus Queries5254 / 6615
- Exponentiation26392 / 28136
- Exponentiation II18489 / 22046
- Counting Divisors24093 / 27169
- Common Divisors15585 / 18022
- Sum of Divisors8778 / 13010
- Divisor Analysis6023 / 8020
- Prime Multiples6993 / 8135
- Counting Coprime Pairs4621 / 5344
- Next Prime2176 / 2492
- Binomial Coefficients11238 / 12434
- Creating Strings II9368 / 9874
- Distributing Apples8928 / 9596
- Christmas Party7342 / 7851
- Permutation Order1037 / 1060
- Permutation Rounds1446 / 1609
- Bracket Sequences I4964 / 5398
- Bracket Sequences II2623 / 2994
- Counting Necklaces2410 / 2604
- Counting Grids2007 / 2131
- Fibonacci Numbers7484 / 9353
- Throwing Dice3909 / 4244
- Graph Paths I3769 / 4032
- Graph Paths II3150 / 3298
- System of Linear Equations522 / 570
- Sum of Four Squares760 / 890
- Triangle Number Sums650 / 787
- Dice Probability3341 / 3597
- Moving Robots1738 / 1835
- Candy Lottery1673 / 3289
- Inversion Probability476 / 2445
- Stick Game3813 / 3903
- Nim Game I5088 / 5271
- Nim Game II4019 / 4176
- Stair Game2739 / 2970
- Grundy's Game1903 / 2491
- Another Game2153 / 2315
String Algorithms
- Word Combinations6473 / 9273
- String Matching12467 / 16592
- Finding Borders9147 / 9987
- Finding Periods6497 / 7344
- Minimal Rotation3179 / 4763
- Longest Palindrome4763 / 6255
- All Palindromes713 / 811
- Required Substring1842 / 2760
- Palindrome Queries2240 / 2608
- Finding Patterns2115 / 2963
- Counting Patterns2002 / 2466
- Pattern Positions1686 / 2046
- Distinct Substrings1901 / 2258
- Distinct Subsequences1206 / 1280
- Repeating Substring2053 / 2372
- String Functions1799 / 1884
- Inverse Suffix Array276 / 324
- String Transform596 / 716
- Substring Order I1305 / 1449
- Substring Order II867 / 1123
- Substring Distribution1210 / 1312
Geometry
- Point Location Test7975 / 8880
- Line Segment Intersection4729 / 5912
- Polygon Area5452 / 5758
- Point in Polygon3011 / 3822
- Polygon Lattice Points2533 / 2616
- Minimum Euclidean Distance2184 / 3087
- Convex Hull3661 / 4361
- Maximum Manhattan Distances662 / 685
- All Manhattan Distances659 / 717
- Intersection Points2156 / 2326
- Line Segments Trace I366 / 380
- Line Segments Trace II304 / 322
- Lines and Queries I419 / 437
- Lines and Queries II362 / 374
- Area of Rectangles1244 / 1389
- Robot Path333 / 619
Advanced Techniques
- Meet in the Middle7251 / 9964
- Hamming Distance3424 / 3745
- Corner Subgrid Check369 / 564
- Corner Subgrid Count2368 / 2664
- Reachable Nodes2442 / 2624
- Reachability Queries1633 / 1921
- Cut and Paste1670 / 1849
- Substring Reversals1454 / 1576
- Reversals and Sums1476 / 1581
- Necessary Roads2137 / 2193
- Necessary Cities1988 / 2079
- Eulerian Subgraphs861 / 905
- Monster Game I1261 / 1401
- Monster Game II1120 / 1197
- Subarray Squares1574 / 1840
- Houses and Schools848 / 1013
- Knuth Division1028 / 1158
- Apples and Bananas1179 / 1280
- One Bit Positions915 / 997
- Signal Processing881 / 943
- New Roads Queries2394 / 2893
- Dynamic Connectivity1100 / 1237
- Parcel Delivery844 / 928
- Task Assignment979 / 1053
- Distinct Routes II639 / 726
Sliding Window Problems
- Sliding Window Sum6111 / 6339
- Sliding Window Minimum4556 / 5204
- Sliding Window Xor4477 / 4539
- Sliding Window Or1982 / 3374
- Sliding Window Distinct Values3068 / 3736
- Sliding Window Mode2473 / 2631
- Sliding Window Mex2295 / 2423
- Sliding Window Median14367 / 16390
- Sliding Window Cost9402 / 10840
- Sliding Window Inversions1282 / 1359
- Sliding Window Advertisement244 / 390
Interactive Problems
- Hidden Integer2420 / 2518
- Hidden Permutation1034 / 1212
- K-th Highest Score457 / 555
- Permuted Binary Strings561 / 576
- Colored Chairs511 / 539
- Inversion Sorting290 / 324
Bitwise Operations
- Counting Bits5405 / 6987
- Maximum Xor Subarray3215 / 3674
- Maximum Xor Subset1084 / 1184
- Number of Subset Xors951 / 971
- K Subset Xors480 / 572
- All Subarray Xors294 / 481
- Xor Pyramid Peak2175 / 2628
- Xor Pyramid Diagonal340 / 380
- Xor Pyramid Row293 / 344
- SOS Bit Problem2286 / 2427
- And Subset Count458 / 476
Construction Problems
- Inverse Inversions1786 / 1902
- Monotone Subsequences1077 / 1270
- Third Permutation439 / 530
- Permutation Prime Sums438 / 473
- Chess Tournament1262 / 1462
- Distinct Sums Grid139 / 215
- Filling Trominos247 / 448
- Grid Path Construction124 / 443
Advanced Graph Problems
- Nearest Shops757 / 977
- Prüfer Code1603 / 1721
- Tree Traversals1299 / 1430
- Course Schedule II2046 / 2923
- Acyclic Graph Edges2309 / 2445
- Strongly Connected Edges1586 / 1870
- Even Outdegree Edges1445 / 1682
- Graph Girth3601 / 4086
- Fixed Length Walk Queries375 / 416
- Transfer Speeds Sum440 / 454
- MST Edge Check679 / 738
- MST Edge Set Check258 / 291
- MST Edge Cost411 / 430
- Network Breakdown1227 / 1335
- Tree Coin Collecting I366 / 398
- Tree Coin Collecting II198 / 231
- Tree Isomorphism I1141 / 1355
- Tree Isomorphism II937 / 1080
- Flight Route Requests522 / 643
- Critical Cities447 / 686
- Visiting Cities713 / 938
- Graph Coloring239 / 279
- Bus Companies282 / 290
- Split into Two Paths101 / 185
- Network Renovation969 / 1287
- Forbidden Cities880 / 1149
- Creating Offices437 / 571
- New Flight Routes347 / 925
Counting Problems
- Filled Subgrid Count I616 / 692
- Filled Subgrid Count II333 / 410
- All Letter Subgrid Count I185 / 278
- All Letter Subgrid Count II146 / 186
- Border Subgrid Count I99 / 172
- Border Subgrid Count II108 / 127
- Raab Game II111 / 128
- Empty String1764 / 2142
- Permutation Inversions1070 / 1181
- Counting Bishops413 / 460
- Counting Sequences699 / 753
- Grid Paths II795 / 995
- Counting Permutations929 / 1048
- Grid Completion234 / 298
- Counting Reorders258 / 368
- Tournament Graph Distribution112 / 119
- Collecting Numbers Distribution122 / 130
- Functional Graph Distribution254 / 313
Additional Problems I
- Shortest Subsequence3096 / 4074
- Distinct Values Sum702 / 726
- Distinct Values Splits504 / 535
- Swap Game2107 / 2709
- Beautiful Permutation II569 / 866
- Multiplication Table7144 / 7957
- Bubble Sort Rounds I427 / 488
- Bubble Sort Rounds II284 / 320
- Nearest Campsites I189 / 220
- Nearest Campsites II186 / 199
- Advertisement4566 / 4837
- Special Substrings1014 / 1113
- Counting LCM Arrays285 / 311
- Square Subsets232 / 257
- Subarray Sum Constraints432 / 460
- Water Containers Moves184 / 194
- Water Containers Queries218 / 229
- Stack Weights611 / 729
- Maximum Average Subarrays179 / 197
- Subsets with Fixed Average221 / 240
- Two Array Average219 / 246
- Pyramid Array791 / 956
- Permutation Subsequence267 / 275
- Bit Inversions2416 / 2730
- Writing Numbers763 / 824
- Letter Pair Move Game211 / 291
- Maximum Building I2155 / 2247
- Sorting Methods799 / 853
- Cyclic Array1254 / 1426
- List of Sums509 / 659
Additional Problems II
- Bouncing Ball Steps242 / 268
- Bouncing Ball Cycle95 / 134
- Knight Moves Queries122 / 147
- K Subset Sums I197 / 252
- K Subset Sums II110 / 145
- Increasing Array II834 / 951
- Food Division539 / 647
- Swap Round Sorting426 / 525
- Binary Subsequences297 / 433
- School Excursion1435 / 1518
- Coin Grid927 / 1081
- Grid Coloring II143 / 186
- Programmers and Artists522 / 731
- Removing Digits II220 / 479
- Coin Arrangement343 / 457
- Replace with Difference135 / 161
- Grid Puzzle I561 / 614
- Grid Puzzle II541 / 593
- Bit Substrings411 / 497
- Reversal Sorting366 / 443
- Book Shop II1291 / 1469
- GCD Subsets424 / 436
- Minimum Cost Pairs147 / 191
- Same Sum Subsets119 / 233
- Mex Grid Queries876 / 1026
- Maximum Building II461 / 568
- Stick Divisions3925 / 4594
- Stick Difference65 / 266
- Coding Company1557 / 2037
- Two Stacks Sorting184 / 591