General
Introductory Problems
- Weird Algorithm167955 / 175575
- Missing Number145049 / 151743
- Repetitions126173 / 131017
- Increasing Array118835 / 122873
- Permutations104309 / 107358
- Number Spiral73879 / 80255
- Two Knights56867 / 58587
- Two Sets61839 / 66283
- Bit Strings70538 / 74323
- Trailing Zeros65453 / 69502
- Coin Piles58126 / 63354
- Palindrome Reorder54058 / 56942
- Gray Code36710 / 41036
- Tower of Hanoi34165 / 35483
- Creating Strings45560 / 46690
- Apple Division46102 / 51823
- Chessboard and Queens27999 / 28477
- Raab Game I6540 / 7383
- Mex Grid Construction6359 / 6682
- Knight Moves Grid6397 / 6540
- Grid Coloring I5373 / 5562
- Digit Queries19709 / 22695
- String Reorder4847 / 5573
- Grid Path Description11014 / 14168
Sorting and Searching
- Distinct Numbers83238 / 89701
- Apartments62318 / 68752
- Ferris Wheel59871 / 64261
- Concert Tickets48062 / 55602
- Restaurant Customers48879 / 52596
- Movie Festival47323 / 49987
- Sum of Two Values54965 / 61231
- Maximum Subarray Sum52700 / 54935
- Stick Lengths47120 / 49187
- Missing Coin Sum35881 / 37148
- Collecting Numbers36754 / 39208
- Collecting Numbers II15847 / 19945
- Playlist36728 / 41723
- Towers36793 / 39313
- Traffic Lights28574 / 31832
- Distinct Values Subarrays8693 / 9905
- Distinct Values Subsequences6673 / 7316
- Josephus Problem I22056 / 24178
- Josephus Problem II12028 / 16491
- Nested Ranges Check13016 / 14816
- Nested Ranges Count8759 / 10278
- Room Allocation21530 / 24590
- Factory Machines31110 / 33705
- Tasks and Deadlines24829 / 25330
- Reading Books20096 / 21475
- Sum of Three Values29298 / 32287
- Sum of Four Values18246 / 20188
- Nearest Smaller Values24475 / 25282
- Subarray Sums I32426 / 34471
- Subarray Sums II29582 / 34810
- Subarray Divisibility26754 / 29008
- Distinct Values Subarrays II16304 / 17793
- Array Division25364 / 26631
- Movie Festival II13673 / 16381
- Maximum Subarray Sum II12723 / 15073
Dynamic Programming
- Dice Combinations86831 / 91722
- Minimizing Coins75014 / 80389
- Coin Combinations I68649 / 74096
- Coin Combinations II58089 / 65423
- Removing Digits64597 / 65863
- Grid Paths I60769 / 62425
- Book Shop54530 / 59732
- Array Description40235 / 44501
- Counting Towers24733 / 26167
- Edit Distance40235 / 42389
- Longest Common Subsequence12372 / 12805
- Rectangle Cutting33154 / 36104
- Minimal Grid Path5544 / 9540
- Money Sums39171 / 40604
- Removal Game23848 / 31266
- Two Sets II30802 / 33042
- Mountain Range3873 / 6797
- Increasing Subsequence31444 / 35207
- Projects21920 / 24395
- Elevator Rides14143 / 17638
- Counting Tilings8330 / 9038
- Counting Numbers12123 / 13524
- Increasing Subsequence II5335 / 6203
Graph Algorithms
- Counting Rooms59941 / 62854
- Labyrinth42023 / 49805
- Building Roads52297 / 54126
- Message Route45187 / 46913
- Building Teams42700 / 44889
- Round Trip33715 / 36579
- Monsters23582 / 27475
- Shortest Routes I37268 / 40852
- Shortest Routes II30110 / 33592
- High Score18872 / 25959
- Flight Discount24226 / 28089
- Cycle Finding17123 / 20732
- Flight Routes16627 / 18469
- Round Trip II18660 / 20837
- Course Schedule24813 / 26115
- Longest Flight Route17855 / 21771
- Game Routes19644 / 20937
- Investigation14679 / 15717
- Planets Queries I12734 / 14808
- Planets Queries II4660 / 5836
- Planets Cycles7796 / 8670
- Road Reparation19211 / 19993
- Road Construction21088 / 21750
- Flight Routes Check16747 / 18076
- Planets and Kingdoms13620 / 14142
- Giant Pizza5741 / 6282
- Coin Collector8928 / 9823
- Mail Delivery7242 / 7899
- De Bruijn Sequence3845 / 4022
- Teleporters Path5577 / 6319
- Hamiltonian Flights8451 / 9584
- Knight's Tour3222 / 3875
- Download Speed5616 / 7397
- Police Chase4466 / 4980
- School Dance4899 / 5170
- Distinct Routes3467 / 4489
Range Queries
- Static Range Sum Queries41952 / 43815
- Static Range Minimum Queries29031 / 31064
- Dynamic Range Sum Queries30098 / 31399
- Dynamic Range Minimum Queries27245 / 27886
- Range Xor Queries28012 / 28388
- Range Update Queries22419 / 23988
- Forest Queries23003 / 23812
- Hotel Queries16285 / 17222
- List Removals13535 / 14192
- Salary Queries10322 / 12881
- Prefix Sum Queries8742 / 9415
- Pizzeria Queries7022 / 7270
- Visible Buildings Queries1943 / 2115
- Range Interval Queries1509 / 2013
- Subarray Sum Queries8144 / 8804
- Subarray Sum Queries II2170 / 2240
- Distinct Values Queries7704 / 9385
- Distinct Values Queries II1252 / 1422
- Increasing Array Queries2951 / 3367
- Movie Festival Queries1609 / 1774
- Forest Queries II4849 / 5197
- Range Updates and Sums6722 / 7905
- Polynomial Queries4963 / 5818
- Range Queries and Copies3526 / 3759
- Missing Coin Sum Queries849 / 1102
Tree Algorithms
- Subordinates34341 / 36715
- Tree Matching19613 / 22690
- Tree Diameter27991 / 29612
- Tree Distances I21527 / 23087
- Tree Distances II17561 / 18351
- Company Queries I19582 / 20590
- Company Queries II18305 / 19252
- Distance Queries16581 / 17759
- Counting Paths10438 / 11030
- Subtree Queries12455 / 13242
- Path Queries10035 / 10604
- Path Queries II4215 / 6230
- Distinct Colors9678 / 10617
- Finding a Centroid7826 / 8143
- Fixed-Length Paths I3883 / 4917
- Fixed-Length Paths II1864 / 3304
Mathematics
- Josephus Queries5446 / 6836
- Exponentiation27058 / 28825
- Exponentiation II18902 / 22509
- Counting Divisors24704 / 27808
- Common Divisors15948 / 18433
- Sum of Divisors9011 / 13316
- Divisor Analysis6199 / 8235
- Prime Multiples7189 / 8346
- Counting Coprime Pairs4761 / 5505
- Next Prime2323 / 2663
- Binomial Coefficients11508 / 12729
- Creating Strings II9588 / 10100
- Distributing Apples9136 / 9806
- Christmas Party7528 / 8047
- Permutation Order1117 / 1145
- Permutation Rounds1570 / 1746
- Bracket Sequences I5079 / 5520
- Bracket Sequences II2688 / 3067
- Counting Necklaces2470 / 2669
- Counting Grids2058 / 2186
- Fibonacci Numbers7653 / 9544
- Throwing Dice4017 / 4358
- Graph Paths I3889 / 4152
- Graph Paths II3246 / 3396
- System of Linear Equations561 / 606
- Sum of Four Squares827 / 966
- Triangle Number Sums698 / 840
- Dice Probability3421 / 3678
- Moving Robots1781 / 1879
- Candy Lottery1750 / 3378
- Inversion Probability509 / 2518
- Stick Game3909 / 4000
- Nim Game I5214 / 5404
- Nim Game II4120 / 4280
- Stair Game2802 / 3041
- Grundy's Game1949 / 2554
- Another Game2205 / 2372
String Algorithms
- Word Combinations6692 / 9551
- String Matching12835 / 17018
- Finding Borders9431 / 10282
- Finding Periods6698 / 7567
- Minimal Rotation3310 / 4911
- Longest Palindrome4924 / 6427
- All Palindromes791 / 890
- Required Substring1907 / 2844
- Palindrome Queries2320 / 2690
- Finding Patterns2196 / 3050
- Counting Patterns2087 / 2559
- Pattern Positions1753 / 2118
- Distinct Substrings1981 / 2349
- Distinct Subsequences1258 / 1334
- Repeating Substring2138 / 2460
- String Functions1875 / 1964
- Inverse Suffix Array324 / 374
- String Transform638 / 762
- Substring Order I1363 / 1509
- Substring Order II906 / 1173
- Substring Distribution1262 / 1365
Geometry
- Point Location Test8171 / 9081
- Line Segment Intersection4833 / 6035
- Polygon Area5576 / 5882
- Point in Polygon3092 / 3911
- Polygon Lattice Points2594 / 2679
- Minimum Euclidean Distance2229 / 3141
- Convex Hull3739 / 4449
- Maximum Manhattan Distances714 / 742
- All Manhattan Distances722 / 791
- Intersection Points2202 / 2374
- Line Segments Trace I399 / 412
- Line Segments Trace II329 / 346
- Lines and Queries I445 / 464
- Lines and Queries II395 / 409
- Area of Rectangles1274 / 1421
- Robot Path341 / 635
Advanced Techniques
- Meet in the Middle7418 / 10154
- Hamming Distance3488 / 3812
- Corner Subgrid Check387 / 592
- Corner Subgrid Count2400 / 2708
- Reachable Nodes2484 / 2669
- Reachability Queries1661 / 1948
- Cut and Paste1698 / 1876
- Substring Reversals1496 / 1619
- Reversals and Sums1520 / 1627
- Necessary Roads2179 / 2236
- Necessary Cities2030 / 2123
- Eulerian Subgraphs874 / 920
- Monster Game I1290 / 1431
- Monster Game II1139 / 1217
- Subarray Squares1616 / 1881
- Houses and Schools884 / 1049
- Knuth Division1062 / 1192
- Apples and Bananas1214 / 1316
- One Bit Positions934 / 1017
- Signal Processing907 / 970
- New Roads Queries2465 / 2975
- Dynamic Connectivity1126 / 1266
- Parcel Delivery872 / 958
- Task Assignment1008 / 1085
- Distinct Routes II664 / 753
Sliding Window Problems
- Sliding Window Sum6725 / 6955
- Sliding Window Minimum5017 / 5732
- Sliding Window Xor4964 / 5033
- Sliding Window Or2217 / 3725
- Sliding Window Distinct Values3440 / 4116
- Sliding Window Mode2748 / 2918
- Sliding Window Mex2561 / 2701
- Sliding Window Median14654 / 16691
- Sliding Window Cost9574 / 11024
- Sliding Window Inversions1393 / 1476
- Sliding Window Advertisement276 / 431
Interactive Problems
- Hidden Integer2603 / 2711
- Hidden Permutation1148 / 1333
- K-th Highest Score517 / 624
- Permuted Binary Strings621 / 636
- Colored Chairs579 / 612
- Inversion Sorting333 / 373
Bitwise Operations
- Counting Bits5655 / 7295
- Maximum Xor Subarray3344 / 3822
- Maximum Xor Subset1162 / 1270
- Number of Subset Xors1024 / 1046
- K Subset Xors530 / 624
- All Subarray Xors318 / 510
- Xor Pyramid Peak2249 / 2714
- Xor Pyramid Diagonal363 / 407
- Xor Pyramid Row315 / 370
- SOS Bit Problem2367 / 2513
- And Subset Count500 / 521
Construction Problems
- Inverse Inversions1883 / 2009
- Monotone Subsequences1141 / 1347
- Third Permutation484 / 583
- Permutation Prime Sums485 / 523
- Chess Tournament1314 / 1517
- Distinct Sums Grid170 / 250
- Filling Trominos278 / 482
- Grid Path Construction149 / 473
Advanced Graph Problems
- Nearest Shops802 / 1033
- Prüfer Code1629 / 1751
- Tree Traversals1332 / 1463
- Course Schedule II2124 / 3014
- Acyclic Graph Edges2346 / 2483
- Strongly Connected Edges1653 / 1936
- Even Outdegree Edges1475 / 1716
- Graph Girth3714 / 4202
- Fixed Length Walk Queries398 / 443
- Transfer Speeds Sum467 / 481
- MST Edge Check737 / 801
- MST Edge Set Check278 / 314
- MST Edge Cost441 / 461
- Network Breakdown1254 / 1365
- Tree Coin Collecting I400 / 433
- Tree Coin Collecting II224 / 258
- Tree Isomorphism I1162 / 1377
- Tree Isomorphism II958 / 1102
- Flight Route Requests537 / 664
- Critical Cities460 / 702
- Visiting Cities726 / 955
- Graph Coloring252 / 295
- Bus Companies299 / 308
- Split into Two Paths113 / 199
- Network Renovation992 / 1308
- Forbidden Cities906 / 1178
- Creating Offices447 / 586
- New Flight Routes358 / 949
Counting Problems
- Filled Subgrid Count I655 / 733
- Filled Subgrid Count II358 / 441
- All Letter Subgrid Count I201 / 296
- All Letter Subgrid Count II154 / 197
- Border Subgrid Count I107 / 189
- Border Subgrid Count II119 / 138
- Raab Game II121 / 139
- Empty String1814 / 2195
- Permutation Inversions1087 / 1199
- Counting Bishops423 / 470
- Counting Sequences724 / 779
- Grid Paths II818 / 1024
- Counting Permutations947 / 1068
- Grid Completion238 / 302
- Counting Reorders273 / 383
- Tournament Graph Distribution123 / 132
- Collecting Numbers Distribution129 / 136
- Functional Graph Distribution258 / 318
Additional Problems I
- Shortest Subsequence3146 / 4134
- Distinct Values Sum752 / 776
- Distinct Values Splits532 / 566
- Swap Game2156 / 2763
- Beautiful Permutation II637 / 965
- Multiplication Table7356 / 8184
- Bubble Sort Rounds I466 / 530
- Bubble Sort Rounds II312 / 349
- Nearest Campsites I203 / 237
- Nearest Campsites II198 / 212
- Advertisement4667 / 4943
- Special Substrings1035 / 1136
- Counting LCM Arrays307 / 337
- Square Subsets245 / 272
- Subarray Sum Constraints466 / 499
- Water Containers Moves198 / 209
- Water Containers Queries232 / 244
- Stack Weights624 / 746
- Maximum Average Subarrays190 / 210
- Subsets with Fixed Average231 / 253
- Two Array Average234 / 262
- Pyramid Array810 / 975
- Permutation Subsequence280 / 289
- Bit Inversions2458 / 2775
- Writing Numbers776 / 839
- Letter Pair Move Game215 / 297
- Maximum Building I2194 / 2287
- Sorting Methods810 / 865
- Cyclic Array1292 / 1464
- List of Sums516 / 670
Additional Problems II
- Bouncing Ball Steps270 / 297
- Bouncing Ball Cycle106 / 148
- Knight Moves Queries134 / 161
- K Subset Sums I214 / 274
- K Subset Sums II125 / 159
- Increasing Array II858 / 978
- Food Division550 / 659
- Swap Round Sorting432 / 535
- Binary Subsequences306 / 443
- School Excursion1471 / 1555
- Coin Grid946 / 1105
- Grid Coloring II149 / 195
- Programmers and Artists536 / 750
- Removing Digits II227 / 493
- Coin Arrangement355 / 472
- Replace with Difference145 / 172
- Grid Puzzle I572 / 627
- Grid Puzzle II556 / 609
- Bit Substrings419 / 508
- Reversal Sorting376 / 454
- Book Shop II1337 / 1520
- GCD Subsets449 / 462
- Minimum Cost Pairs154 / 199
- Same Sum Subsets130 / 256
- Mex Grid Queries893 / 1044
- Maximum Building II467 / 575
- Stick Divisions3989 / 4658
- Stick Difference73 / 278
- Coding Company1583 / 2069
- Two Stacks Sorting189 / 602