General
Introductory Problems
- Weird Algorithm161542 / 168984
- Missing Number139400 / 145992
- Repetitions121345 / 126108
- Increasing Array114133 / 118097
- Permutations100333 / 103321
- Number Spiral70966 / 77207
- Two Knights54417 / 56099
- Two Sets59182 / 63558
- Bit Strings67661 / 71344
- Trailing Zeros62844 / 66772
- Coin Piles55700 / 60830
- Palindrome Reorder51828 / 54660
- Gray Code34896 / 39112
- Tower of Hanoi32437 / 33725
- Creating Strings43696 / 44803
- Apple Division43974 / 49577
- Chessboard and Queens26582 / 27055
- Raab Game I5466 / 6204
- Mex Grid Construction5301 / 5605
- Knight Moves Grid5317 / 5434
- Grid Coloring I4451 / 4608
- Digit Queries18711 / 21656
- String Reorder4062 / 4699
- Grid Path Description10403 / 13476
Sorting and Searching
- Distinct Numbers79855 / 86203
- Apartments59592 / 65937
- Ferris Wheel57199 / 61541
- Concert Tickets45862 / 53230
- Restaurant Customers46674 / 50286
- Movie Festival45110 / 47713
- Sum of Two Values52441 / 58545
- Maximum Subarray Sum50514 / 52710
- Stick Lengths45085 / 47112
- Missing Coin Sum34150 / 35378
- Collecting Numbers35019 / 37409
- Collecting Numbers II14820 / 18810
- Playlist34939 / 39810
- Towers35056 / 37518
- Traffic Lights27228 / 30403
- Distinct Values Subarrays7319 / 8508
- Distinct Values Subsequences5609 / 6193
- Josephus Problem I20878 / 22951
- Josephus Problem II11355 / 15616
- Nested Ranges Check12199 / 13959
- Nested Ranges Count8211 / 9669
- Room Allocation20490 / 23454
- Factory Machines29484 / 32031
- Tasks and Deadlines23601 / 24099
- Reading Books19087 / 20444
- Sum of Three Values27877 / 30801
- Sum of Four Values17341 / 19261
- Nearest Smaller Values23275 / 24069
- Subarray Sums I30889 / 32890
- Subarray Sums II28073 / 33215
- Subarray Divisibility25432 / 27668
- Distinct Values Subarrays II15391 / 16862
- Array Division24135 / 25386
- Movie Festival II12924 / 15551
- Maximum Subarray Sum II12024 / 14310
Dynamic Programming
- Dice Combinations83044 / 87767
- Minimizing Coins71824 / 77063
- Coin Combinations I65655 / 70932
- Coin Combinations II55554 / 62703
- Removing Digits61792 / 63025
- Grid Paths I58081 / 59694
- Book Shop52033 / 57101
- Array Description38330 / 42486
- Counting Towers23434 / 24825
- Edit Distance38446 / 40554
- Longest Common Subsequence10626 / 11020
- Rectangle Cutting31718 / 34594
- Minimal Grid Path4659 / 8278
- Money Sums37516 / 38913
- Removal Game22586 / 29972
- Two Sets II29486 / 31686
- Mountain Range3226 / 5855
- Increasing Subsequence30158 / 33830
- Projects20880 / 23298
- Elevator Rides13387 / 16772
- Counting Tilings7847 / 8538
- Counting Numbers11142 / 12505
- Increasing Subsequence II4845 / 5638
Graph Algorithms
- Counting Rooms57386 / 60236
- Labyrinth39946 / 47611
- Building Roads49955 / 51746
- Message Route43079 / 44769
- Building Teams40671 / 42835
- Round Trip32177 / 34999
- Monsters22259 / 26110
- Shortest Routes I35397 / 38937
- Shortest Routes II28648 / 32049
- High Score17619 / 24574
- Flight Discount22755 / 26526
- Cycle Finding16105 / 19642
- Flight Routes15632 / 17426
- Round Trip II17710 / 19839
- Course Schedule23452 / 24731
- Longest Flight Route16683 / 20518
- Game Routes18550 / 19817
- Investigation13760 / 14767
- Planets Queries I11983 / 14015
- Planets Queries II4346 / 5482
- Planets Cycles7318 / 8147
- Road Reparation18186 / 18955
- Road Construction19963 / 20604
- Flight Routes Check15862 / 17167
- Planets and Kingdoms12721 / 13234
- Giant Pizza5332 / 5854
- Coin Collector8350 / 9218
- Mail Delivery6891 / 7528
- De Bruijn Sequence3640 / 3807
- Teleporters Path5273 / 6004
- Hamiltonian Flights7976 / 9078
- Knight's Tour3002 / 3624
- Download Speed5283 / 7030
- Police Chase4223 / 4725
- School Dance4635 / 4896
- Distinct Routes3265 / 4257
Range Queries
- Static Range Sum Queries40075 / 41846
- Static Range Minimum Queries27849 / 29814
- Dynamic Range Sum Queries28907 / 30183
- Dynamic Range Minimum Queries26169 / 26797
- Range Xor Queries26926 / 27281
- Range Update Queries21484 / 23009
- Forest Queries22042 / 22837
- Hotel Queries15609 / 16533
- List Removals12937 / 13586
- Salary Queries9774 / 12275
- Prefix Sum Queries8307 / 8974
- Pizzeria Queries6691 / 6931
- Visible Buildings Queries1711 / 1869
- Range Interval Queries1332 / 1786
- Subarray Sum Queries7842 / 8490
- Subarray Sum Queries II1903 / 1969
- Distinct Values Queries7366 / 9029
- Distinct Values Queries II1114 / 1268
- Increasing Array Queries2825 / 3231
- Movie Festival Queries1481 / 1645
- Forest Queries II4672 / 5017
- Range Updates and Sums6380 / 7546
- Polynomial Queries4724 / 5549
- Range Queries and Copies3350 / 3577
- Missing Coin Sum Queries766 / 1001
Tree Algorithms
- Subordinates32815 / 35112
- Tree Matching18671 / 21652
- Tree Diameter26725 / 28312
- Tree Distances I20523 / 22043
- Tree Distances II16743 / 17476
- Company Queries I18697 / 19676
- Company Queries II17512 / 18435
- Distance Queries15825 / 16981
- Counting Paths9961 / 10543
- Subtree Queries11938 / 12716
- Path Queries9588 / 10150
- Path Queries II3976 / 5928
- Distinct Colors9226 / 10154
- Finding a Centroid7449 / 7751
- Fixed-Length Paths I3647 / 4657
- Fixed-Length Paths II1729 / 3112
Mathematics
- Josephus Queries5159 / 6494
- Exponentiation26022 / 27757
- Exponentiation II18219 / 21741
- Counting Divisors23722 / 26755
- Common Divisors15330 / 17739
- Sum of Divisors8604 / 12792
- Divisor Analysis5906 / 7883
- Prime Multiples6847 / 7973
- Counting Coprime Pairs4531 / 5248
- Next Prime2065 / 2370
- Binomial Coefficients11031 / 12215
- Creating Strings II9229 / 9734
- Distributing Apples8802 / 9459
- Christmas Party7229 / 7737
- Permutation Order992 / 1014
- Permutation Rounds1355 / 1511
- Bracket Sequences I4897 / 5329
- Bracket Sequences II2591 / 2957
- Counting Necklaces2367 / 2561
- Counting Grids1970 / 2094
- Fibonacci Numbers7400 / 9261
- Throwing Dice3861 / 4197
- Graph Paths I3725 / 3986
- Graph Paths II3114 / 3260
- System of Linear Equations499 / 545
- Sum of Four Squares728 / 855
- Triangle Number Sums620 / 753
- Dice Probability3312 / 3568
- Moving Robots1717 / 1814
- Candy Lottery1640 / 3248
- Inversion Probability454 / 2413
- Stick Game3762 / 3852
- Nim Game I5003 / 5186
- Nim Game II3956 / 4113
- Stair Game2697 / 2928
- Grundy's Game1879 / 2459
- Another Game2113 / 2276
String Algorithms
- Word Combinations6345 / 9117
- String Matching12255 / 16336
- Finding Borders8990 / 9822
- Finding Periods6373 / 7214
- Minimal Rotation3098 / 4675
- Longest Palindrome4664 / 6147
- All Palindromes670 / 762
- Required Substring1788 / 2700
- Palindrome Queries2191 / 2555
- Finding Patterns2052 / 2896
- Counting Patterns1942 / 2400
- Pattern Positions1635 / 1987
- Distinct Substrings1849 / 2202
- Distinct Subsequences1158 / 1232
- Repeating Substring1995 / 2313
- String Functions1741 / 1825
- Inverse Suffix Array249 / 294
- String Transform568 / 686
- Substring Order I1257 / 1401
- Substring Order II830 / 1079
- Substring Distribution1168 / 1267
Geometry
- Point Location Test7872 / 8768
- Line Segment Intersection4666 / 5843
- Polygon Area5383 / 5689
- Point in Polygon2962 / 3766
- Polygon Lattice Points2500 / 2583
- Minimum Euclidean Distance2145 / 3042
- Convex Hull3620 / 4315
- Maximum Manhattan Distances639 / 661
- All Manhattan Distances627 / 685
- Intersection Points2114 / 2278
- Line Segments Trace I341 / 353
- Line Segments Trace II281 / 297
- Lines and Queries I390 / 408
- Lines and Queries II338 / 349
- Area of Rectangles1221 / 1363
- Robot Path327 / 607
Advanced Techniques
- Meet in the Middle7136 / 9827
- Hamming Distance3393 / 3709
- Corner Subgrid Check353 / 539
- Corner Subgrid Count2342 / 2629
- Reachable Nodes2410 / 2590
- Reachability Queries1606 / 1888
- Cut and Paste1639 / 1816
- Substring Reversals1425 / 1545
- Reversals and Sums1446 / 1550
- Necessary Roads2094 / 2151
- Necessary Cities1935 / 2025
- Eulerian Subgraphs848 / 892
- Monster Game I1231 / 1367
- Monster Game II1090 / 1166
- Subarray Squares1533 / 1797
- Houses and Schools821 / 981
- Knuth Division1005 / 1133
- Apples and Bananas1149 / 1245
- One Bit Positions898 / 979
- Signal Processing860 / 920
- New Roads Queries2341 / 2828
- Dynamic Connectivity1067 / 1202
- Parcel Delivery821 / 906
- Task Assignment953 / 1028
- Distinct Routes II620 / 706
Sliding Window Problems
- Sliding Window Sum5812 / 6028
- Sliding Window Minimum4337 / 4958
- Sliding Window Xor4237 / 4295
- Sliding Window Or1871 / 3209
- Sliding Window Distinct Values2887 / 3543
- Sliding Window Mode2354 / 2499
- Sliding Window Mex2168 / 2288
- Sliding Window Median14229 / 16237
- Sliding Window Cost9326 / 10754
- Sliding Window Inversions1218 / 1294
- Sliding Window Advertisement231 / 366
Interactive Problems
- Hidden Integer2306 / 2398
- Hidden Permutation978 / 1145
- K-th Highest Score430 / 520
- Permuted Binary Strings530 / 544
- Colored Chairs481 / 507
- Inversion Sorting277 / 309
Bitwise Operations
- Counting Bits5272 / 6816
- Maximum Xor Subarray3144 / 3581
- Maximum Xor Subset1020 / 1112
- Number of Subset Xors908 / 927
- K Subset Xors454 / 541
- All Subarray Xors280 / 459
- Xor Pyramid Peak2132 / 2579
- Xor Pyramid Diagonal324 / 362
- Xor Pyramid Row273 / 322
- SOS Bit Problem2242 / 2385
- And Subset Count437 / 454
Construction Problems
- Inverse Inversions1745 / 1855
- Monotone Subsequences1048 / 1237
- Third Permutation415 / 505
- Permutation Prime Sums419 / 453
- Chess Tournament1246 / 1442
- Distinct Sums Grid132 / 205
- Filling Trominos244 / 439
- Grid Path Construction121 / 438
Advanced Graph Problems
- Nearest Shops715 / 924
- Prüfer Code1584 / 1701
- Tree Traversals1283 / 1414
- Course Schedule II1989 / 2844
- Acyclic Graph Edges2278 / 2414
- Strongly Connected Edges1553 / 1834
- Even Outdegree Edges1409 / 1644
- Graph Girth3545 / 4030
- Fixed Length Walk Queries360 / 398
- Transfer Speeds Sum421 / 434
- MST Edge Check636 / 693
- MST Edge Set Check238 / 270
- MST Edge Cost390 / 408
- Network Breakdown1192 / 1300
- Tree Coin Collecting I340 / 372
- Tree Coin Collecting II182 / 212
- Tree Isomorphism I1128 / 1345
- Tree Isomorphism II927 / 1071
- Flight Route Requests512 / 632
- Critical Cities436 / 673
- Visiting Cities699 / 923
- Graph Coloring228 / 268
- Bus Companies265 / 272
- Split into Two Paths95 / 172
- Network Renovation960 / 1275
- Forbidden Cities869 / 1134
- Creating Offices424 / 554
- New Flight Routes339 / 910
Counting Problems
- Filled Subgrid Count I583 / 656
- Filled Subgrid Count II309 / 382
- All Letter Subgrid Count I167 / 257
- All Letter Subgrid Count II133 / 171
- Border Subgrid Count I89 / 156
- Border Subgrid Count II99 / 116
- Raab Game II105 / 120
- Empty String1716 / 2087
- Permutation Inversions1056 / 1165
- Counting Bishops402 / 448
- Counting Sequences669 / 723
- Grid Paths II777 / 972
- Counting Permutations912 / 1029
- Grid Completion229 / 290
- Counting Reorders247 / 356
- Tournament Graph Distribution105 / 112
- Collecting Numbers Distribution111 / 119
- Functional Graph Distribution249 / 307
Additional Problems I
- Shortest Subsequence3063 / 4036
- Distinct Values Sum662 / 685
- Distinct Values Splits478 / 508
- Swap Game2076 / 2674
- Beautiful Permutation II529 / 810
- Multiplication Table7031 / 7826
- Bubble Sort Rounds I399 / 457
- Bubble Sort Rounds II260 / 295
- Nearest Campsites I176 / 205
- Nearest Campsites II172 / 184
- Advertisement4508 / 4778
- Special Substrings999 / 1096
- Counting LCM Arrays272 / 298
- Square Subsets221 / 246
- Subarray Sum Constraints389 / 415
- Water Containers Moves170 / 180
- Water Containers Queries207 / 217
- Stack Weights598 / 713
- Maximum Average Subarrays164 / 181
- Subsets with Fixed Average206 / 223
- Two Array Average203 / 227
- Pyramid Array770 / 933
- Permutation Subsequence246 / 254
- Bit Inversions2374 / 2686
- Writing Numbers750 / 810
- Letter Pair Move Game205 / 283
- Maximum Building I2126 / 2217
- Sorting Methods786 / 840
- Cyclic Array1230 / 1400
- List of Sums499 / 649
Additional Problems II
- Bouncing Ball Steps229 / 251
- Bouncing Ball Cycle89 / 127
- Knight Moves Queries114 / 137
- K Subset Sums I183 / 239
- K Subset Sums II102 / 134
- Increasing Array II813 / 929
- Food Division526 / 634
- Swap Round Sorting420 / 517
- Binary Subsequences295 / 430
- School Excursion1409 / 1493
- Coin Grid901 / 1052
- Grid Coloring II135 / 176
- Programmers and Artists511 / 714
- Removing Digits II216 / 473
- Coin Arrangement339 / 452
- Replace with Difference128 / 153
- Grid Puzzle I545 / 600
- Grid Puzzle II521 / 575
- Bit Substrings404 / 490
- Reversal Sorting360 / 435
- Book Shop II1262 / 1438
- GCD Subsets408 / 420
- Minimum Cost Pairs138 / 181
- Same Sum Subsets111 / 213
- Mex Grid Queries865 / 1013
- Maximum Building II453 / 558
- Stick Divisions3890 / 4556
- Stick Difference57 / 249
- Coding Company1531 / 2005
- Two Stacks Sorting180 / 582