General
Introductory Problems
- Weird Algorithm167960 / 175581
- Missing Number145052 / 151746
- Repetitions126176 / 131020
- Increasing Array118838 / 122876
- Permutations104312 / 107362
- Number Spiral73880 / 80256
- Two Knights56867 / 58587
- Two Sets61842 / 66286
- Bit Strings70538 / 74323
- Trailing Zeros65453 / 69502
- Coin Piles58127 / 63356
- Palindrome Reorder54058 / 56943
- Gray Code36712 / 41038
- Tower of Hanoi34168 / 35485
- Creating Strings45563 / 46692
- Apple Division46107 / 51829
- Chessboard and Queens28000 / 28478
- Raab Game I6540 / 7383
- Mex Grid Construction6359 / 6682
- Knight Moves Grid6398 / 6541
- Grid Coloring I5373 / 5562
- Digit Queries19709 / 22695
- String Reorder4848 / 5573
- Grid Path Description11014 / 14168
Sorting and Searching
- Distinct Numbers83239 / 89702
- Apartments62320 / 68755
- Ferris Wheel59873 / 64264
- Concert Tickets48065 / 55606
- Restaurant Customers48879 / 52596
- Movie Festival47325 / 49989
- Sum of Two Values54965 / 61232
- Maximum Subarray Sum52700 / 54935
- Stick Lengths47120 / 49187
- Missing Coin Sum35882 / 37149
- Collecting Numbers36756 / 39210
- Collecting Numbers II15848 / 19946
- Playlist36728 / 41724
- Towers36797 / 39317
- Traffic Lights28574 / 31833
- Distinct Values Subarrays8694 / 9907
- Distinct Values Subsequences6673 / 7316
- Josephus Problem I22056 / 24178
- Josephus Problem II12029 / 16492
- Nested Ranges Check13017 / 14817
- Nested Ranges Count8760 / 10278
- Room Allocation21531 / 24591
- Factory Machines31111 / 33706
- Tasks and Deadlines24829 / 25330
- Reading Books20096 / 21475
- Sum of Three Values29298 / 32287
- Sum of Four Values18246 / 20188
- Nearest Smaller Values24475 / 25282
- Subarray Sums I32428 / 34473
- Subarray Sums II29584 / 34812
- Subarray Divisibility26755 / 29010
- Distinct Values Subarrays II16305 / 17794
- Array Division25365 / 26632
- Movie Festival II13674 / 16382
- Maximum Subarray Sum II12725 / 15075
Dynamic Programming
- Dice Combinations86832 / 91722
- Minimizing Coins75015 / 80390
- Coin Combinations I68650 / 74096
- Coin Combinations II58089 / 65424
- Removing Digits64600 / 65866
- Grid Paths I60772 / 62428
- Book Shop54532 / 59734
- Array Description40237 / 44503
- Counting Towers24734 / 26168
- Edit Distance40235 / 42389
- Longest Common Subsequence12375 / 12808
- Rectangle Cutting33154 / 36105
- Minimal Grid Path5546 / 9543
- Money Sums39172 / 40605
- Removal Game23849 / 31267
- Two Sets II30802 / 33042
- Mountain Range3875 / 6798
- Increasing Subsequence31445 / 35209
- Projects21920 / 24395
- Elevator Rides14143 / 17639
- Counting Tilings8331 / 9039
- Counting Numbers12124 / 13525
- Increasing Subsequence II5335 / 6203
Graph Algorithms
- Counting Rooms59942 / 62855
- Labyrinth42025 / 49806
- Building Roads52300 / 54129
- Message Route45187 / 46913
- Building Teams42700 / 44889
- Round Trip33717 / 36582
- Monsters23585 / 27476
- Shortest Routes I37272 / 40857
- Shortest Routes II30110 / 33592
- High Score18873 / 25960
- Flight Discount24228 / 28093
- Cycle Finding17125 / 20733
- Flight Routes16630 / 18471
- Round Trip II18660 / 20838
- Course Schedule24814 / 26116
- Longest Flight Route17855 / 21772
- Game Routes19644 / 20937
- Investigation14679 / 15717
- Planets Queries I12735 / 14809
- Planets Queries II4660 / 5837
- Planets Cycles7797 / 8670
- Road Reparation19212 / 19994
- Road Construction21089 / 21751
- Flight Routes Check16747 / 18076
- Planets and Kingdoms13624 / 14146
- Giant Pizza5741 / 6282
- Coin Collector8929 / 9824
- Mail Delivery7242 / 7899
- De Bruijn Sequence3845 / 4022
- Teleporters Path5577 / 6319
- Hamiltonian Flights8451 / 9584
- Knight's Tour3222 / 3875
- Download Speed5617 / 7398
- Police Chase4467 / 4981
- School Dance4899 / 5170
- Distinct Routes3467 / 4489
Range Queries
- Static Range Sum Queries41954 / 43817
- Static Range Minimum Queries29034 / 31067
- Dynamic Range Sum Queries30100 / 31401
- Dynamic Range Minimum Queries27246 / 27887
- Range Xor Queries28013 / 28389
- Range Update Queries22420 / 23988
- Forest Queries23008 / 23817
- Hotel Queries16287 / 17224
- List Removals13538 / 14195
- Salary Queries10323 / 12881
- Prefix Sum Queries8743 / 9416
- Pizzeria Queries7022 / 7270
- Visible Buildings Queries1943 / 2115
- Range Interval Queries1510 / 2013
- Subarray Sum Queries8144 / 8804
- Subarray Sum Queries II2171 / 2241
- Distinct Values Queries7704 / 9385
- Distinct Values Queries II1252 / 1422
- Increasing Array Queries2951 / 3367
- Movie Festival Queries1609 / 1774
- Forest Queries II4849 / 5197
- Range Updates and Sums6723 / 7907
- Polynomial Queries4963 / 5819
- Range Queries and Copies3526 / 3759
- Missing Coin Sum Queries849 / 1102
Tree Algorithms
- Subordinates34345 / 36718
- Tree Matching19615 / 22692
- Tree Diameter27993 / 29614
- Tree Distances I21530 / 23090
- Tree Distances II17562 / 18352
- Company Queries I19585 / 20593
- Company Queries II18306 / 19253
- Distance Queries16583 / 17761
- Counting Paths10438 / 11030
- Subtree Queries12457 / 13244
- Path Queries10036 / 10605
- Path Queries II4216 / 6231
- Distinct Colors9678 / 10617
- Finding a Centroid7826 / 8143
- Fixed-Length Paths I3883 / 4917
- Fixed-Length Paths II1864 / 3304
Mathematics
- Josephus Queries5447 / 6837
- Exponentiation27059 / 28826
- Exponentiation II18902 / 22509
- Counting Divisors24705 / 27809
- Common Divisors15950 / 18435
- Sum of Divisors9011 / 13316
- Divisor Analysis6199 / 8235
- Prime Multiples7191 / 8348
- Counting Coprime Pairs4761 / 5505
- Next Prime2323 / 2663
- Binomial Coefficients11510 / 12731
- Creating Strings II9588 / 10100
- Distributing Apples9137 / 9807
- Christmas Party7529 / 8048
- Permutation Order1118 / 1146
- Permutation Rounds1570 / 1746
- Bracket Sequences I5081 / 5522
- Bracket Sequences II2688 / 3067
- Counting Necklaces2470 / 2669
- Counting Grids2059 / 2187
- 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 / 17019
- Finding Borders9432 / 10283
- Finding Periods6698 / 7567
- Minimal Rotation3311 / 4911
- Longest Palindrome4925 / 6428
- 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 Distance2230 / 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 Middle7419 / 10156
- Hamming Distance3488 / 3812
- Corner Subgrid Check387 / 592
- Corner Subgrid Count2401 / 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 Or2218 / 3726
- Sliding Window Distinct Values3440 / 4116
- Sliding Window Mode2748 / 2918
- Sliding Window Mex2562 / 2702
- Sliding Window Median14655 / 16692
- Sliding Window Cost9574 / 11024
- Sliding Window Inversions1394 / 1477
- 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 Subarray3345 / 3823
- 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 II2125 / 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 Inversions2459 / 2776
- 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 / 536
- 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