General
Introductory Problems
- Weird Algorithm168017 / 175639
- Missing Number145101 / 151794
- Repetitions126212 / 131057
- Increasing Array118881 / 122919
- Permutations104338 / 107388
- Number Spiral73899 / 80277
- Two Knights56889 / 58608
- Two Sets61867 / 66311
- Bit Strings70563 / 74349
- Trailing Zeros65468 / 69520
- Coin Piles58148 / 63376
- Palindrome Reorder54082 / 56966
- Gray Code36726 / 41049
- Tower of Hanoi34183 / 35502
- Creating Strings45579 / 46708
- Apple Division46127 / 51853
- Chessboard and Queens28017 / 28496
- Raab Game I6547 / 7393
- Mex Grid Construction6367 / 6692
- Knight Moves Grid6402 / 6548
- Grid Coloring I5377 / 5568
- Digit Queries19716 / 22706
- String Reorder4849 / 5575
- Grid Path Description11018 / 14172
Sorting and Searching
- Distinct Numbers83272 / 89735
- Apartments62347 / 68782
- Ferris Wheel59905 / 64296
- Concert Tickets48084 / 55624
- Restaurant Customers48907 / 52622
- Movie Festival47349 / 50015
- Sum of Two Values54984 / 61248
- Maximum Subarray Sum52718 / 54954
- Stick Lengths47142 / 49210
- Missing Coin Sum35900 / 37168
- Collecting Numbers36770 / 39227
- Collecting Numbers II15858 / 19953
- Playlist36748 / 41744
- Towers36812 / 39332
- Traffic Lights28584 / 31846
- Distinct Values Subarrays8708 / 9922
- Distinct Values Subsequences6679 / 7325
- Josephus Problem I22063 / 24186
- Josephus Problem II12033 / 16499
- Nested Ranges Check13027 / 14825
- Nested Ranges Count8767 / 10285
- Room Allocation21542 / 24605
- Factory Machines31125 / 33721
- Tasks and Deadlines24854 / 25355
- Reading Books20115 / 21497
- Sum of Three Values29312 / 32303
- Sum of Four Values18255 / 20197
- Nearest Smaller Values24488 / 25295
- Subarray Sums I32448 / 34492
- Subarray Sums II29597 / 34829
- Subarray Divisibility26767 / 29024
- Distinct Values Subarrays II16312 / 17802
- Array Division25374 / 26641
- Movie Festival II13678 / 16387
- Maximum Subarray Sum II12732 / 15083
Dynamic Programming
- Dice Combinations86875 / 91763
- Minimizing Coins75056 / 80432
- Coin Combinations I68687 / 74130
- Coin Combinations II58125 / 65459
- Removing Digits64633 / 65901
- Grid Paths I60805 / 62461
- Book Shop54570 / 59771
- Array Description40265 / 44530
- Counting Towers24754 / 26189
- Edit Distance40260 / 42413
- Longest Common Subsequence12398 / 12831
- Rectangle Cutting33178 / 36128
- Minimal Grid Path5562 / 9563
- Money Sums39192 / 40625
- Removal Game23865 / 31283
- Two Sets II30817 / 33058
- Mountain Range3888 / 6809
- Increasing Subsequence31457 / 35223
- Projects21930 / 24405
- Elevator Rides14156 / 17654
- Counting Tilings8338 / 9047
- Counting Numbers12134 / 13534
- Increasing Subsequence II5339 / 6209
Graph Algorithms
- Counting Rooms59975 / 62892
- Labyrinth42053 / 49833
- Building Roads52321 / 54149
- Message Route45205 / 46932
- Building Teams42710 / 44899
- Round Trip33727 / 36594
- Monsters23596 / 27488
- Shortest Routes I37291 / 40876
- Shortest Routes II30125 / 33609
- High Score18888 / 25982
- Flight Discount24243 / 28106
- Cycle Finding17139 / 20746
- Flight Routes16639 / 18480
- Round Trip II18672 / 20852
- Course Schedule24828 / 26132
- Longest Flight Route17869 / 21790
- Game Routes19657 / 20952
- Investigation14682 / 15719
- Planets Queries I12740 / 14814
- Planets Queries II4664 / 5842
- Planets Cycles7803 / 8674
- Road Reparation19229 / 20011
- Road Construction21106 / 21769
- Flight Routes Check16762 / 18093
- Planets and Kingdoms13641 / 14163
- Giant Pizza5748 / 6290
- Coin Collector8938 / 9832
- Mail Delivery7247 / 7904
- De Bruijn Sequence3850 / 4028
- Teleporters Path5582 / 6325
- Hamiltonian Flights8457 / 9592
- Knight's Tour3224 / 3878
- Download Speed5622 / 7404
- Police Chase4469 / 4984
- School Dance4904 / 5176
- Distinct Routes3469 / 4492
Range Queries
- Static Range Sum Queries41976 / 43839
- Static Range Minimum Queries29045 / 31079
- Dynamic Range Sum Queries30114 / 31415
- Dynamic Range Minimum Queries27259 / 27900
- Range Xor Queries28029 / 28404
- Range Update Queries22432 / 23999
- Forest Queries23020 / 23829
- Hotel Queries16293 / 17230
- List Removals13544 / 14201
- Salary Queries10331 / 12890
- Prefix Sum Queries8750 / 9423
- Pizzeria Queries7026 / 7276
- Visible Buildings Queries1945 / 2118
- Range Interval Queries1511 / 2015
- Subarray Sum Queries8151 / 8811
- Subarray Sum Queries II2175 / 2246
- Distinct Values Queries7707 / 9388
- Distinct Values Queries II1257 / 1428
- Increasing Array Queries2952 / 3370
- Movie Festival Queries1609 / 1775
- Forest Queries II4850 / 5199
- Range Updates and Sums6729 / 7914
- Polynomial Queries4966 / 5822
- Range Queries and Copies3529 / 3763
- Missing Coin Sum Queries851 / 1104
Tree Algorithms
- Subordinates34362 / 36734
- Tree Matching19630 / 22706
- Tree Diameter28017 / 29638
- Tree Distances I21544 / 23103
- Tree Distances II17571 / 18361
- Company Queries I19603 / 20612
- Company Queries II18321 / 19268
- Distance Queries16594 / 17772
- Counting Paths10447 / 11043
- Subtree Queries12466 / 13253
- Path Queries10042 / 10611
- Path Queries II4217 / 6233
- Distinct Colors9680 / 10619
- Finding a Centroid7831 / 8148
- Fixed-Length Paths I3884 / 4918
- Fixed-Length Paths II1864 / 3305
Mathematics
- Josephus Queries5452 / 6842
- Exponentiation27071 / 28838
- Exponentiation II18910 / 22517
- Counting Divisors24722 / 27835
- Common Divisors15960 / 18445
- Sum of Divisors9014 / 13322
- Divisor Analysis6202 / 8239
- Prime Multiples7193 / 8350
- Counting Coprime Pairs4761 / 5506
- Next Prime2328 / 2667
- Binomial Coefficients11512 / 12733
- Creating Strings II9593 / 10105
- Distributing Apples9140 / 9810
- Christmas Party7530 / 8050
- Permutation Order1119 / 1148
- Permutation Rounds1577 / 1752
- Bracket Sequences I5083 / 5524
- Bracket Sequences II2690 / 3070
- Counting Necklaces2470 / 2671
- Counting Grids2060 / 2189
- Fibonacci Numbers7654 / 9545
- Throwing Dice4020 / 4361
- Graph Paths I3889 / 4152
- Graph Paths II3249 / 3399
- System of Linear Equations562 / 609
- Sum of Four Squares829 / 969
- Triangle Number Sums699 / 843
- Dice Probability3422 / 3680
- Moving Robots1781 / 1880
- Candy Lottery1751 / 3380
- Inversion Probability510 / 2520
- Stick Game3910 / 4002
- Nim Game I5215 / 5406
- Nim Game II4120 / 4281
- Stair Game2802 / 3042
- Grundy's Game1949 / 2555
- Another Game2205 / 2373
String Algorithms
- Word Combinations6693 / 9552
- String Matching12846 / 17030
- Finding Borders9439 / 10291
- Finding Periods6703 / 7572
- Minimal Rotation3314 / 4914
- Longest Palindrome4928 / 6431
- All Palindromes793 / 892
- Required Substring1907 / 2845
- Palindrome Queries2322 / 2692
- Finding Patterns2198 / 3053
- Counting Patterns2088 / 2560
- Pattern Positions1755 / 2120
- Distinct Substrings1982 / 2350
- Distinct Subsequences1259 / 1336
- Repeating Substring2140 / 2462
- String Functions1876 / 1966
- Inverse Suffix Array324 / 375
- String Transform638 / 763
- Substring Order I1363 / 1509
- Substring Order II907 / 1173
- Substring Distribution1263 / 1366
Geometry
- Point Location Test8172 / 9083
- Line Segment Intersection4835 / 6038
- Polygon Area5577 / 5884
- Point in Polygon3093 / 3913
- Polygon Lattice Points2595 / 2681
- Minimum Euclidean Distance2230 / 3143
- Convex Hull3739 / 4451
- Maximum Manhattan Distances716 / 745
- All Manhattan Distances722 / 793
- Intersection Points2202 / 2375
- Line Segments Trace I399 / 413
- Line Segments Trace II329 / 347
- Lines and Queries I445 / 465
- Lines and Queries II395 / 410
- Area of Rectangles1274 / 1422
- Robot Path341 / 636
Advanced Techniques
- Meet in the Middle7424 / 10161
- Hamming Distance3488 / 3812
- Corner Subgrid Check387 / 593
- Corner Subgrid Count2401 / 2709
- Reachable Nodes2485 / 2671
- Reachability Queries1662 / 1950
- Cut and Paste1698 / 1877
- Substring Reversals1496 / 1620
- Reversals and Sums1520 / 1628
- Necessary Roads2180 / 2238
- Necessary Cities2031 / 2125
- Eulerian Subgraphs874 / 921
- Monster Game I1291 / 1433
- Monster Game II1139 / 1218
- Subarray Squares1617 / 1883
- Houses and Schools884 / 1050
- Knuth Division1063 / 1195
- Apples and Bananas1214 / 1317
- One Bit Positions934 / 1018
- Signal Processing907 / 971
- New Roads Queries2466 / 2977
- Dynamic Connectivity1126 / 1267
- Parcel Delivery872 / 959
- Task Assignment1008 / 1086
- Distinct Routes II664 / 754
Sliding Window Problems
- Sliding Window Sum6736 / 6967
- Sliding Window Minimum5028 / 5743
- Sliding Window Xor4973 / 5042
- Sliding Window Or2222 / 3735
- Sliding Window Distinct Values3448 / 4124
- Sliding Window Mode2756 / 2926
- Sliding Window Mex2571 / 2712
- Sliding Window Median14658 / 16695
- Sliding Window Cost9580 / 11029
- Sliding Window Inversions1396 / 1480
- Sliding Window Advertisement278 / 436
Interactive Problems
- Hidden Integer2606 / 2715
- Hidden Permutation1150 / 1336
- K-th Highest Score517 / 625
- Permuted Binary Strings622 / 638
- Colored Chairs579 / 613
- Inversion Sorting333 / 374
Bitwise Operations
- Counting Bits5662 / 7302
- Maximum Xor Subarray3349 / 3830
- Maximum Xor Subset1163 / 1271
- Number of Subset Xors1025 / 1047
- K Subset Xors530 / 625
- All Subarray Xors318 / 511
- Xor Pyramid Peak2249 / 2716
- Xor Pyramid Diagonal363 / 408
- Xor Pyramid Row315 / 371
- SOS Bit Problem2368 / 2515
- And Subset Count500 / 522
Construction Problems
- Inverse Inversions1885 / 2012
- Monotone Subsequences1141 / 1349
- Third Permutation484 / 584
- Permutation Prime Sums486 / 525
- Chess Tournament1315 / 1519
- Distinct Sums Grid171 / 252
- Filling Trominos279 / 484
- Grid Path Construction150 / 475
Advanced Graph Problems
- Nearest Shops802 / 1034
- Prüfer Code1629 / 1752
- Tree Traversals1333 / 1465
- Course Schedule II2128 / 3018
- Acyclic Graph Edges2346 / 2484
- Strongly Connected Edges1653 / 1937
- Even Outdegree Edges1475 / 1717
- Graph Girth3714 / 4203
- Fixed Length Walk Queries398 / 444
- Transfer Speeds Sum467 / 482
- MST Edge Check737 / 803
- MST Edge Set Check278 / 315
- MST Edge Cost441 / 462
- Network Breakdown1255 / 1367
- Tree Coin Collecting I401 / 435
- Tree Coin Collecting II225 / 260
- Tree Isomorphism I1163 / 1380
- Tree Isomorphism II958 / 1103
- Flight Route Requests537 / 665
- Critical Cities460 / 703
- Visiting Cities726 / 956
- Graph Coloring252 / 296
- Bus Companies299 / 309
- Split into Two Paths113 / 200
- Network Renovation992 / 1309
- Forbidden Cities906 / 1179
- Creating Offices447 / 587
- New Flight Routes358 / 950
Counting Problems
- Filled Subgrid Count I657 / 736
- Filled Subgrid Count II358 / 442
- All Letter Subgrid Count I201 / 299
- All Letter Subgrid Count II154 / 199
- Border Subgrid Count I107 / 190
- Border Subgrid Count II119 / 139
- Raab Game II121 / 140
- Empty String1814 / 2197
- Permutation Inversions1087 / 1200
- Counting Bishops423 / 471
- Counting Sequences724 / 780
- Grid Paths II819 / 1026
- Counting Permutations948 / 1070
- Grid Completion238 / 303
- Counting Reorders273 / 385
- Tournament Graph Distribution123 / 133
- Collecting Numbers Distribution129 / 137
- Functional Graph Distribution258 / 319
Additional Problems I
- Shortest Subsequence3147 / 4135
- Distinct Values Sum753 / 777
- Distinct Values Splits532 / 566
- Swap Game2157 / 2764
- Beautiful Permutation II638 / 967
- Multiplication Table7360 / 8189
- Bubble Sort Rounds I468 / 533
- Bubble Sort Rounds II314 / 352
- Nearest Campsites I204 / 239
- Nearest Campsites II199 / 214
- Advertisement4670 / 4947
- Special Substrings1036 / 1138
- Counting LCM Arrays309 / 339
- Square Subsets245 / 273
- Subarray Sum Constraints467 / 502
- Water Containers Moves198 / 210
- Water Containers Queries232 / 245
- Stack Weights624 / 747
- Maximum Average Subarrays190 / 211
- Subsets with Fixed Average231 / 254
- Two Array Average234 / 263
- Pyramid Array810 / 976
- Permutation Subsequence280 / 290
- Bit Inversions2459 / 2777
- Writing Numbers776 / 840
- Letter Pair Move Game215 / 298
- Maximum Building I2196 / 2290
- Sorting Methods810 / 866
- Cyclic Array1292 / 1465
- List of Sums516 / 671
Additional Problems II
- Bouncing Ball Steps270 / 298
- Bouncing Ball Cycle107 / 150
- Knight Moves Queries134 / 162
- K Subset Sums I214 / 275
- K Subset Sums II125 / 160
- Increasing Array II859 / 980
- Food Division550 / 660
- Swap Round Sorting432 / 537
- Binary Subsequences306 / 444
- School Excursion1471 / 1556
- Coin Grid946 / 1106
- Grid Coloring II149 / 196
- Programmers and Artists536 / 751
- Removing Digits II227 / 494
- Coin Arrangement355 / 473
- Replace with Difference145 / 173
- Grid Puzzle I573 / 629
- Grid Puzzle II557 / 611
- Bit Substrings419 / 509
- Reversal Sorting376 / 455
- Book Shop II1338 / 1522
- GCD Subsets449 / 463
- Minimum Cost Pairs154 / 200
- Same Sum Subsets130 / 257
- Mex Grid Queries893 / 1045
- Maximum Building II467 / 576
- Stick Divisions3991 / 4661
- Stick Difference73 / 279
- Coding Company1584 / 2071
- Two Stacks Sorting189 / 604