General
Introductory Problems
- Weird Algorithm163733 / 171239
- Missing Number141326 / 147962
- Repetitions122924 / 127715
- Increasing Array115697 / 119689
- Permutations101588 / 104589
- Number Spiral71864 / 78153
- Two Knights55150 / 56847
- Two Sets60013 / 64412
- Bit Strings68594 / 72319
- Trailing Zeros63630 / 67593
- Coin Piles56458 / 61603
- Palindrome Reorder52497 / 55349
- Gray Code35489 / 39738
- Tower of Hanoi32956 / 34256
- Creating Strings44288 / 45404
- Apple Division44711 / 50362
- Chessboard and Queens27001 / 27480
- Raab Game I5780 / 6562
- Mex Grid Construction5629 / 5941
- Knight Moves Grid5662 / 5786
- Grid Coloring I4734 / 4899
- Digit Queries19034 / 22002
- String Reorder4293 / 4967
- Grid Path Description10570 / 13668
Sorting and Searching
- Distinct Numbers80967 / 87363
- Apartments60463 / 66839
- Ferris Wheel58008 / 62362
- Concert Tickets46529 / 53969
- Restaurant Customers47337 / 50983
- Movie Festival45788 / 48414
- Sum of Two Values53298 / 59487
- Maximum Subarray Sum51198 / 53410
- Stick Lengths45743 / 47792
- Missing Coin Sum34696 / 35935
- Collecting Numbers35540 / 37950
- Collecting Numbers II15116 / 19138
- Playlist35534 / 40455
- Towers35567 / 38052
- Traffic Lights27629 / 30836
- Distinct Values Subarrays7753 / 8951
- Distinct Values Subsequences5923 / 6532
- Josephus Problem I21243 / 23333
- Josephus Problem II11545 / 15874
- Nested Ranges Check12452 / 14222
- Nested Ranges Count8372 / 9846
- Room Allocation20806 / 23799
- Factory Machines30029 / 32601
- Tasks and Deadlines23984 / 24480
- Reading Books19408 / 20774
- Sum of Three Values28316 / 31277
- Sum of Four Values17616 / 19538
- Nearest Smaller Values23657 / 24457
- Subarray Sums I31388 / 33411
- Subarray Sums II28547 / 33728
- Subarray Divisibility25842 / 28083
- Distinct Values Subarrays II15674 / 17148
- Array Division24523 / 25771
- Movie Festival II13162 / 15832
- Maximum Subarray Sum II12234 / 14545
Dynamic Programming
- Dice Combinations84299 / 89111
- Minimizing Coins72869 / 78175
- Coin Combinations I66613 / 71964
- Coin Combinations II56371 / 63589
- Removing Digits62667 / 63917
- Grid Paths I58974 / 60612
- Book Shop52822 / 57948
- Array Description38908 / 43105
- Counting Towers23809 / 25213
- Edit Distance38961 / 41104
- Longest Common Subsequence11117 / 11524
- Rectangle Cutting32101 / 35003
- Minimal Grid Path4900 / 8637
- Money Sums37981 / 39398
- Removal Game22934 / 30311
- Two Sets II29868 / 32085
- Mountain Range3410 / 6124
- Increasing Subsequence30498 / 34212
- Projects21182 / 23619
- Elevator Rides13602 / 17023
- Counting Tilings7986 / 8685
- Counting Numbers11422 / 12796
- Increasing Subsequence II4996 / 5812
Graph Algorithms
- Counting Rooms58243 / 61116
- Labyrinth40600 / 48316
- Building Roads50755 / 52562
- Message Route43758 / 45461
- Building Teams41343 / 43515
- Round Trip32664 / 35497
- Monsters22675 / 26542
- Shortest Routes I36052 / 39607
- Shortest Routes II29115 / 32547
- High Score18007 / 25010
- Flight Discount23274 / 27083
- Cycle Finding16442 / 20004
- Flight Routes15956 / 17765
- Round Trip II17993 / 20150
- Course Schedule23975 / 25269
- Longest Flight Route17095 / 20969
- Game Routes18887 / 20163
- Investigation14085 / 15107
- Planets Queries I12198 / 14249
- Planets Queries II4441 / 5591
- Planets Cycles7465 / 8311
- Road Reparation18519 / 19287
- Road Construction20382 / 21030
- Flight Routes Check16154 / 17472
- Planets and Kingdoms13032 / 13551
- Giant Pizza5462 / 5994
- Coin Collector8553 / 9433
- Mail Delivery7010 / 7656
- De Bruijn Sequence3711 / 3883
- Teleporters Path5379 / 6115
- Hamiltonian Flights8127 / 9244
- Knight's Tour3086 / 3725
- Download Speed5392 / 7151
- Police Chase4305 / 4814
- School Dance4732 / 4997
- Distinct Routes3336 / 4338
Range Queries
- Static Range Sum Queries40753 / 42572
- Static Range Minimum Queries28243 / 30234
- Dynamic Range Sum Queries29327 / 30609
- Dynamic Range Minimum Queries26536 / 27166
- Range Xor Queries27317 / 27690
- Range Update Queries21811 / 23353
- Forest Queries22353 / 23151
- Hotel Queries15840 / 16770
- List Removals13144 / 13802
- Salary Queries9979 / 12495
- Prefix Sum Queries8484 / 9155
- Pizzeria Queries6816 / 7060
- Visible Buildings Queries1805 / 1969
- Range Interval Queries1392 / 1872
- Subarray Sum Queries7962 / 8615
- Subarray Sum Queries II2014 / 2083
- Distinct Values Queries7496 / 9167
- Distinct Values Queries II1169 / 1328
- Increasing Array Queries2882 / 3292
- Movie Festival Queries1536 / 1701
- Forest Queries II4748 / 5097
- Range Updates and Sums6500 / 7673
- Polynomial Queries4806 / 5641
- Range Queries and Copies3414 / 3644
- Missing Coin Sum Queries793 / 1033
Tree Algorithms
- Subordinates33284 / 35609
- Tree Matching18970 / 21985
- Tree Diameter27162 / 28765
- Tree Distances I20835 / 22371
- Tree Distances II16995 / 17780
- Company Queries I18963 / 19952
- Company Queries II17742 / 18670
- Distance Queries16044 / 17204
- Counting Paths10085 / 10671
- Subtree Queries12098 / 12875
- Path Queries9734 / 10296
- Path Queries II4066 / 6041
- Distinct Colors9383 / 10315
- Finding a Centroid7575 / 7879
- Fixed-Length Paths I3731 / 4751
- Fixed-Length Paths II1775 / 3181
Mathematics
- Josephus Queries5251 / 6611
- Exponentiation26381 / 28125
- Exponentiation II18483 / 22038
- Counting Divisors24086 / 27160
- Common Divisors15579 / 18015
- Sum of Divisors8774 / 13006
- Divisor Analysis6022 / 8019
- Prime Multiples6992 / 8133
- Counting Coprime Pairs4619 / 5343
- Next Prime2173 / 2489
- Binomial Coefficients11234 / 12431
- Creating Strings II9362 / 9868
- Distributing Apples8922 / 9585
- Christmas Party7338 / 7847
- Permutation Order1036 / 1059
- Permutation Rounds1445 / 1608
- Bracket Sequences I4962 / 5396
- Bracket Sequences II2622 / 2993
- Counting Necklaces2409 / 2603
- Counting Grids2006 / 2130
- Fibonacci Numbers7484 / 9352
- 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 Robots1737 / 1834
- Candy Lottery1672 / 3288
- Inversion Probability476 / 2443
- Stick Game3812 / 3902
- Nim Game I5087 / 5270
- Nim Game II4018 / 4176
- Stair Game2739 / 2970
- Grundy's Game1903 / 2491
- Another Game2153 / 2315
String Algorithms
- Word Combinations6471 / 9271
- String Matching12463 / 16588
- Finding Borders9145 / 9985
- Finding Periods6495 / 7343
- Minimal Rotation3176 / 4760
- Longest Palindrome4761 / 6253
- All Palindromes713 / 810
- Required Substring1841 / 2759
- Palindrome Queries2240 / 2608
- Finding Patterns2115 / 2962
- Counting Patterns2002 / 2466
- Pattern Positions1686 / 2046
- Distinct Substrings1901 / 2258
- Distinct Subsequences1206 / 1280
- Repeating Substring2053 / 2372
- String Functions1796 / 1881
- Inverse Suffix Array275 / 323
- String Transform596 / 716
- Substring Order I1304 / 1448
- Substring Order II865 / 1122
- Substring Distribution1210 / 1312
Geometry
- Point Location Test7974 / 8879
- Line Segment Intersection4727 / 5910
- Polygon Area5449 / 5755
- Point in Polygon3010 / 3821
- Polygon Lattice Points2533 / 2616
- Minimum Euclidean Distance2184 / 3087
- Convex Hull3661 / 4361
- Maximum Manhattan Distances661 / 684
- 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 Middle7247 / 9960
- Hamming Distance3423 / 3744
- Corner Subgrid Check368 / 563
- Corner Subgrid Count2366 / 2663
- Reachable Nodes2441 / 2623
- Reachability Queries1632 / 1919
- Cut and Paste1669 / 1848
- Substring Reversals1454 / 1576
- Reversals and Sums1476 / 1581
- Necessary Roads2137 / 2193
- Necessary Cities1988 / 2079
- Eulerian Subgraphs861 / 905
- Monster Game I1259 / 1399
- Monster Game II1119 / 1196
- Subarray Squares1573 / 1839
- Houses and Schools848 / 1013
- Knuth Division1028 / 1158
- Apples and Bananas1179 / 1280
- One Bit Positions914 / 996
- Signal Processing880 / 942
- New Roads Queries2393 / 2891
- Dynamic Connectivity1098 / 1235
- Parcel Delivery843 / 927
- Task Assignment978 / 1052
- Distinct Routes II638 / 725
Sliding Window Problems
- Sliding Window Sum6107 / 6335
- Sliding Window Minimum4551 / 5197
- Sliding Window Xor4474 / 4536
- Sliding Window Or1981 / 3372
- Sliding Window Distinct Values3064 / 3732
- Sliding Window Mode2473 / 2631
- Sliding Window Mex2289 / 2418
- Sliding Window Median14367 / 16390
- Sliding Window Cost9401 / 10839
- Sliding Window Inversions1281 / 1358
- Sliding Window Advertisement244 / 390
Interactive Problems
- Hidden Integer2419 / 2517
- Hidden Permutation1034 / 1212
- K-th Highest Score457 / 555
- Permuted Binary Strings561 / 576
- Colored Chairs511 / 539
- Inversion Sorting290 / 324
Bitwise Operations
- Counting Bits5403 / 6986
- Maximum Xor Subarray3215 / 3674
- Maximum Xor Subset1083 / 1183
- Number of Subset Xors951 / 970
- K Subset Xors480 / 572
- All Subarray Xors294 / 481
- Xor Pyramid Peak2173 / 2627
- Xor Pyramid Diagonal340 / 380
- Xor Pyramid Row293 / 344
- SOS Bit Problem2286 / 2427
- And Subset Count458 / 476
Construction Problems
- Inverse Inversions1785 / 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 II2045 / 2922
- Acyclic Graph Edges2309 / 2445
- Strongly Connected Edges1586 / 1870
- Even Outdegree Edges1445 / 1682
- Graph Girth3600 / 4085
- Fixed Length Walk Queries375 / 416
- Transfer Speeds Sum440 / 454
- MST Edge Check678 / 737
- 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 / 685
- 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 String1761 / 2140
- Permutation Inversions1070 / 1181
- Counting Bishops413 / 460
- Counting Sequences698 / 752
- Grid Paths II795 / 995
- Counting Permutations928 / 1047
- Grid Completion234 / 298
- Counting Reorders258 / 368
- Tournament Graph Distribution111 / 118
- Collecting Numbers Distribution121 / 129
- Functional Graph Distribution254 / 313
Additional Problems I
- Shortest Subsequence3095 / 4073
- Distinct Values Sum701 / 725
- Distinct Values Splits504 / 535
- Swap Game2107 / 2709
- Beautiful Permutation II569 / 865
- Multiplication Table7141 / 7954
- Bubble Sort Rounds I427 / 488
- Bubble Sort Rounds II284 / 320
- Nearest Campsites I189 / 220
- Nearest Campsites II186 / 199
- Advertisement4563 / 4834
- Special Substrings1013 / 1112
- Counting LCM Arrays285 / 311
- Square Subsets232 / 257
- Subarray Sum Constraints432 / 460
- Water Containers Moves184 / 194
- Water Containers Queries218 / 229
- Stack Weights610 / 728
- Maximum Average Subarrays179 / 197
- Subsets with Fixed Average221 / 240
- Two Array Average219 / 246
- Pyramid Array791 / 956
- Permutation Subsequence267 / 275
- Bit Inversions2414 / 2728
- 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 Steps241 / 267
- Bouncing Ball Cycle95 / 134
- Knight Moves Queries122 / 147
- K Subset Sums I196 / 251
- K Subset Sums II110 / 144
- Increasing Array II833 / 950
- Food Division539 / 646
- Swap Round Sorting426 / 525
- Binary Subsequences297 / 433
- School Excursion1435 / 1518
- Coin Grid926 / 1080
- Grid Coloring II143 / 186
- Programmers and Artists522 / 731
- Removing Digits II219 / 478
- Coin Arrangement343 / 457
- Replace with Difference135 / 161
- Grid Puzzle I561 / 614
- Grid Puzzle II540 / 592
- Bit Substrings411 / 497
- Reversal Sorting366 / 442
- Book Shop II1291 / 1469
- GCD Subsets423 / 435
- Minimum Cost Pairs147 / 191
- Same Sum Subsets118 / 232
- Mex Grid Queries875 / 1025
- Maximum Building II461 / 568
- Stick Divisions3924 / 4592
- Stick Difference64 / 265
- Coding Company1557 / 2037
- Two Stacks Sorting184 / 591