General
Introductory Problems
- Weird Algorithm169979 / 177663
- Missing Number146839 / 153571
- Repetitions127678 / 132560
- Increasing Array120312 / 124382
- Permutations105549 / 108629
- Number Spiral74820 / 81233
- Two Knights57661 / 59381
- Two Sets62659 / 67122
- Bit Strings71417 / 75231
- Trailing Zeros66231 / 70305
- Coin Piles58869 / 64124
- Palindrome Reorder54697 / 57598
- Gray Code37232 / 41567
- Tower of Hanoi34672 / 36003
- Creating Strings46127 / 47259
- Apple Division46713 / 52464
- Chessboard and Queens28420 / 28901
- Raab Game I6840 / 7721
- Mex Grid Construction6647 / 6978
- Knight Moves Grid6701 / 6851
- Grid Coloring I5638 / 5838
- Digit Queries19993 / 22990
- String Reorder5073 / 5817
- Grid Path Description11169 / 14356
Sorting and Searching
- Distinct Numbers84340 / 90847
- Apartments63281 / 69741
- Ferris Wheel60802 / 65224
- Concert Tickets48831 / 56431
- Restaurant Customers49652 / 53384
- Movie Festival48168 / 50846
- Sum of Two Values55888 / 62199
- Maximum Subarray Sum53482 / 55728
- Stick Lengths47919 / 49998
- Missing Coin Sum36516 / 37786
- Collecting Numbers37377 / 39862
- Collecting Numbers II16242 / 20356
- Playlist37366 / 42416
- Towers37413 / 39949
- Traffic Lights29046 / 32348
- Distinct Values Subarrays9168 / 10385
- Distinct Values Subsequences7039 / 7707
- Josephus Problem I22485 / 24618
- Josephus Problem II12276 / 16817
- Nested Ranges Check13340 / 15145
- Nested Ranges Count8951 / 10489
- Room Allocation21958 / 25042
- Factory Machines31710 / 34327
- Tasks and Deadlines25358 / 25860
- Reading Books20544 / 21945
- Sum of Three Values29879 / 32895
- Sum of Four Values18626 / 20589
- Nearest Smaller Values24957 / 25775
- Subarray Sums I33053 / 35115
- Subarray Sums II30114 / 35393
- Subarray Divisibility27253 / 29525
- Distinct Values Subarrays II16627 / 18122
- Array Division25810 / 27084
- Movie Festival II13970 / 16703
- Maximum Subarray Sum II12997 / 15370
Dynamic Programming
- Dice Combinations88203 / 93124
- Minimizing Coins76299 / 81708
- Coin Combinations I69743 / 75221
- Coin Combinations II59072 / 66462
- Removing Digits65635 / 66920
- Grid Paths I61762 / 63427
- Book Shop55546 / 60785
- Array Description41018 / 45313
- Counting Towers25351 / 26802
- Edit Distance41032 / 43207
- Longest Common Subsequence13099 / 13554
- Rectangle Cutting33831 / 36818
- Minimal Grid Path5940 / 10108
- Money Sums39967 / 41406
- Removal Game24426 / 31868
- Two Sets II31427 / 33686
- Mountain Range4130 / 7190
- Increasing Subsequence32039 / 35844
- Projects22371 / 24860
- Elevator Rides14508 / 18054
- Counting Tilings8532 / 9239
- Counting Numbers12578 / 13988
- Increasing Subsequence II5559 / 6476
Graph Algorithms
- Counting Rooms61015 / 63941
- Labyrinth43049 / 50883
- Building Roads53384 / 55217
- Message Route46172 / 47903
- Building Teams43614 / 45814
- Round Trip34505 / 37400
- Monsters24228 / 28150
- Shortest Routes I38060 / 41654
- Shortest Routes II30797 / 34309
- High Score19465 / 26595
- Flight Discount24957 / 28844
- Cycle Finding17616 / 21237
- Flight Routes17182 / 19033
- Round Trip II19175 / 21380
- Course Schedule25475 / 26783
- Longest Flight Route18444 / 22393
- Game Routes20225 / 21525
- Investigation15167 / 16223
- Planets Queries I13150 / 15256
- Planets Queries II4822 / 6031
- Planets Cycles8043 / 8917
- Road Reparation19766 / 20559
- Road Construction21623 / 22293
- Flight Routes Check17182 / 18525
- Planets and Kingdoms13939 / 14538
- Giant Pizza5902 / 6448
- Coin Collector9221 / 10120
- Mail Delivery7421 / 8080
- De Bruijn Sequence3943 / 4123
- Teleporters Path5735 / 6483
- Hamiltonian Flights8697 / 9849
- Knight's Tour3306 / 3967
- Download Speed5746 / 7532
- Police Chase4558 / 5074
- School Dance5004 / 5276
- Distinct Routes3550 / 4579
Range Queries
- Static Range Sum Queries42668 / 44554
- Static Range Minimum Queries29455 / 31512
- Dynamic Range Sum Queries30610 / 31933
- Dynamic Range Minimum Queries27704 / 28361
- Range Xor Queries28457 / 28834
- Range Update Queries22821 / 24403
- Forest Queries23465 / 24286
- Hotel Queries16609 / 17557
- List Removals13786 / 14453
- Salary Queries10566 / 13137
- Prefix Sum Queries8915 / 9593
- Pizzeria Queries7155 / 7407
- Visible Buildings Queries2041 / 2217
- Range Interval Queries1561 / 2090
- Subarray Sum Queries8284 / 8950
- Subarray Sum Queries II2277 / 2349
- Distinct Values Queries7834 / 9522
- Distinct Values Queries II1294 / 1470
- Increasing Array Queries2993 / 3413
- Movie Festival Queries1640 / 1807
- Forest Queries II4920 / 5271
- Range Updates and Sums6837 / 8028
- Polynomial Queries5038 / 5901
- Range Queries and Copies3572 / 3810
- Missing Coin Sum Queries811 / 1129
Tree Algorithms
- Subordinates35026 / 37432
- Tree Matching20087 / 23187
- Tree Diameter28559 / 30190
- Tree Distances I22073 / 23645
- Tree Distances II18004 / 18813
- Company Queries I20137 / 21153
- Company Queries II18820 / 19778
- Distance Queries17038 / 18223
- Counting Paths10748 / 11354
- Subtree Queries12747 / 13545
- Path Queries10272 / 10844
- Path Queries II4314 / 6359
- Distinct Colors9888 / 10832
- Finding a Centroid8005 / 8329
- Fixed-Length Paths I3981 / 5025
- Fixed-Length Paths II1917 / 3380
Mathematics
- Josephus Queries5567 / 6968
- Exponentiation27518 / 29299
- Exponentiation II19221 / 22857
- Counting Divisors25091 / 28235
- Common Divisors16198 / 18706
- Sum of Divisors9170 / 13514
- Divisor Analysis6314 / 8372
- Prime Multiples7315 / 8475
- Counting Coprime Pairs4837 / 5586
- Next Prime2428 / 2777
- Binomial Coefficients11760 / 12999
- Creating Strings II9739 / 10254
- Distributing Apples9276 / 9949
- Christmas Party7718 / 8236
- Permutation Order1173 / 1207
- Permutation Rounds1677 / 1860
- Bracket Sequences I5161 / 5606
- Bracket Sequences II2731 / 3117
- Counting Necklaces2509 / 2712
- Counting Grids2096 / 2226
- Fibonacci Numbers7768 / 9677
- Throwing Dice4091 / 4435
- Graph Paths I3957 / 4221
- Graph Paths II3312 / 3467
- System of Linear Equations585 / 638
- Sum of Four Squares867 / 1009
- Triangle Number Sums729 / 879
- Dice Probability3469 / 3728
- Moving Robots1805 / 1904
- Candy Lottery1803 / 3439
- Inversion Probability529 / 2562
- Stick Game3970 / 4062
- Nim Game I5288 / 5480
- Nim Game II4183 / 4348
- Stair Game2843 / 3084
- Grundy's Game1985 / 2594
- Another Game2244 / 2415
String Algorithms
- Word Combinations6821 / 9698
- String Matching13055 / 17274
- Finding Borders9608 / 10463
- Finding Periods6838 / 7718
- Minimal Rotation3390 / 5002
- Longest Palindrome5024 / 6545
- All Palindromes841 / 942
- Required Substring1931 / 2873
- Palindrome Queries2366 / 2738
- Finding Patterns2231 / 3094
- Counting Patterns2118 / 2591
- Pattern Positions1782 / 2147
- Distinct Substrings2004 / 2373
- Distinct Subsequences1278 / 1355
- Repeating Substring2171 / 2496
- String Functions1907 / 2001
- Inverse Suffix Array337 / 387
- String Transform647 / 772
- Substring Order I1379 / 1525
- Substring Order II922 / 1190
- Substring Distribution1274 / 1378
Geometry
- Point Location Test8280 / 9199
- Line Segment Intersection4915 / 6123
- Polygon Area5653 / 5967
- Point in Polygon3149 / 3973
- Polygon Lattice Points2552 / 2737
- Minimum Euclidean Distance2256 / 3172
- Convex Hull3778 / 4489
- Maximum Manhattan Distances752 / 782
- All Manhattan Distances765 / 845
- Intersection Points2230 / 2404
- Line Segments Trace I420 / 434
- Line Segments Trace II347 / 366
- Lines and Queries I460 / 483
- Lines and Queries II407 / 428
- Area of Rectangles1292 / 1442
- Robot Path350 / 650
Advanced Techniques
- Meet in the Middle7529 / 10281
- Hamming Distance3527 / 3855
- Corner Subgrid Check250 / 622
- Corner Subgrid Count2430 / 2745
- Reachable Nodes2508 / 2693
- Reachability Queries1681 / 1971
- Cut and Paste1715 / 1895
- Substring Reversals1510 / 1637
- Reversals and Sums1535 / 1643
- Necessary Roads2213 / 2271
- Necessary Cities2058 / 2151
- Eulerian Subgraphs884 / 931
- Monster Game I1312 / 1456
- Monster Game II1158 / 1238
- Subarray Squares1649 / 1916
- Houses and Schools899 / 1065
- Knuth Division1074 / 1207
- Apples and Bananas1230 / 1333
- One Bit Positions945 / 1029
- Signal Processing919 / 983
- New Roads Queries2500 / 3012
- Dynamic Connectivity1148 / 1288
- Parcel Delivery888 / 975
- Task Assignment1023 / 1103
- Distinct Routes II673 / 763
Sliding Window Problems
- Sliding Window Sum7074 / 7311
- Sliding Window Minimum5288 / 6030
- Sliding Window Xor5221 / 5294
- Sliding Window Or2341 / 3906
- Sliding Window Distinct Values3645 / 4325
- Sliding Window Mode2893 / 3064
- Sliding Window Mex2718 / 2860
- Sliding Window Median14820 / 16864
- Sliding Window Cost9690 / 11144
- Sliding Window Inversions1476 / 1564
- Sliding Window Advertisement289 / 456
Interactive Problems
- Hidden Integer2674 / 2786
- Hidden Permutation1181 / 1370
- K-th Highest Score527 / 637
- Permuted Binary Strings633 / 650
- Colored Chairs588 / 624
- Inversion Sorting340 / 381
Bitwise Operations
- Counting Bits5794 / 7458
- Maximum Xor Subarray3441 / 3930
- Maximum Xor Subset1216 / 1332
- Number of Subset Xors1068 / 1090
- K Subset Xors555 / 652
- All Subarray Xors332 / 527
- Xor Pyramid Peak2297 / 2770
- Xor Pyramid Diagonal377 / 422
- Xor Pyramid Row326 / 381
- SOS Bit Problem2416 / 2562
- And Subset Count525 / 547
Construction Problems
- Inverse Inversions1927 / 2058
- Monotone Subsequences1164 / 1377
- Third Permutation490 / 606
- Permutation Prime Sums500 / 539
- Chess Tournament1329 / 1535
- Distinct Sums Grid177 / 260
- Filling Trominos288 / 495
- Grid Path Construction154 / 477
Advanced Graph Problems
- Nearest Shops835 / 1078
- Prüfer Code1653 / 1776
- Tree Traversals1350 / 1482
- Course Schedule II2182 / 3082
- Acyclic Graph Edges2377 / 2515
- Strongly Connected Edges1680 / 1966
- Even Outdegree Edges1494 / 1737
- Graph Girth3780 / 4273
- Fixed Length Walk Queries417 / 463
- Transfer Speeds Sum481 / 496
- MST Edge Check764 / 831
- MST Edge Set Check291 / 327
- MST Edge Cost457 / 478
- Network Breakdown1273 / 1385
- Tree Coin Collecting I416 / 449
- Tree Coin Collecting II234 / 268
- Tree Isomorphism I1184 / 1401
- Tree Isomorphism II973 / 1118
- Flight Route Requests551 / 679
- Critical Cities472 / 714
- Visiting Cities735 / 966
- Graph Coloring265 / 309
- Bus Companies309 / 319
- Split into Two Paths122 / 213
- Network Renovation1006 / 1325
- Forbidden Cities922 / 1199
- Creating Offices456 / 594
- New Flight Routes372 / 979
Counting Problems
- Filled Subgrid Count I688 / 771
- Filled Subgrid Count II372 / 457
- All Letter Subgrid Count I213 / 309
- All Letter Subgrid Count II160 / 204
- Border Subgrid Count I113 / 196
- Border Subgrid Count II124 / 143
- Raab Game II126 / 145
- Empty String1834 / 2223
- Permutation Inversions1099 / 1212
- Counting Bishops429 / 477
- Counting Sequences733 / 789
- Grid Paths II824 / 1033
- Counting Permutations957 / 1079
- Grid Completion244 / 309
- Counting Reorders282 / 394
- Tournament Graph Distribution128 / 137
- Collecting Numbers Distribution135 / 142
- Functional Graph Distribution265 / 325
Additional Problems I
- Shortest Subsequence3180 / 4172
- Distinct Values Sum778 / 802
- Distinct Values Splits551 / 590
- Swap Game2182 / 2796
- Beautiful Permutation II662 / 1009
- Multiplication Table7456 / 8293
- Bubble Sort Rounds I489 / 557
- Bubble Sort Rounds II330 / 368
- Nearest Campsites I214 / 251
- Nearest Campsites II208 / 223
- Advertisement4756 / 5032
- Special Substrings1045 / 1147
- Counting LCM Arrays328 / 360
- Square Subsets255 / 283
- Subarray Sum Constraints500 / 535
- Water Containers Moves207 / 219
- Water Containers Queries240 / 252
- Stack Weights627 / 751
- Maximum Average Subarrays200 / 221
- Subsets with Fixed Average241 / 264
- Two Array Average242 / 271
- Pyramid Array824 / 991
- Permutation Subsequence287 / 297
- Bit Inversions2484 / 2802
- Writing Numbers788 / 852
- Letter Pair Move Game216 / 303
- Maximum Building I2221 / 2317
- Sorting Methods818 / 874
- Cyclic Array1313 / 1487
- List of Sums519 / 676
Additional Problems II
- Bouncing Ball Steps275 / 304
- Bouncing Ball Cycle113 / 159
- Knight Moves Queries141 / 169
- K Subset Sums I224 / 287
- K Subset Sums II139 / 173
- Increasing Array II867 / 991
- Food Division554 / 664
- Swap Round Sorting436 / 542
- Binary Subsequences308 / 446
- School Excursion1485 / 1570
- Coin Grid967 / 1128
- Grid Coloring II155 / 202
- Programmers and Artists543 / 759
- Removing Digits II232 / 499
- Coin Arrangement358 / 477
- Replace with Difference149 / 179
- Grid Puzzle I578 / 635
- Grid Puzzle II559 / 613
- Bit Substrings425 / 515
- Reversal Sorting379 / 458
- Book Shop II1358 / 1544
- GCD Subsets463 / 477
- Minimum Cost Pairs161 / 205
- Same Sum Subsets139 / 267
- Mex Grid Queries897 / 1049
- Maximum Building II474 / 584
- Stick Divisions4028 / 4705
- Stick Difference81 / 294
- Coding Company1600 / 2091
- Two Stacks Sorting193 / 607