General
Introductory Problems
- Weird Algorithm162276 / 169744
- Missing Number140071 / 146678
- Repetitions121813 / 126588
- Increasing Array114666 / 118642
- Permutations100719 / 103708
- Number Spiral71258 / 77510
- Two Knights54650 / 56342
- Two Sets59473 / 63857
- Bit Strings68026 / 71729
- Trailing Zeros63121 / 67061
- Coin Piles55962 / 61093
- Palindrome Reorder52060 / 54899
- Gray Code35135 / 39362
- Tower of Hanoi32644 / 33931
- Creating Strings43906 / 45017
- Apple Division44195 / 49811
- Chessboard and Queens26732 / 27205
- Raab Game I5565 / 6321
- Mex Grid Construction5400 / 5709
- Knight Moves Grid5429 / 5549
- Grid Coloring I4539 / 4700
- Digit Queries18838 / 21796
- String Reorder4128 / 4781
- Grid Path Description10459 / 13539
Sorting and Searching
- Distinct Numbers80223 / 86588
- Apartments59881 / 66235
- Ferris Wheel57463 / 61808
- Concert Tickets46101 / 53499
- Restaurant Customers46906 / 50534
- Movie Festival45326 / 47937
- Sum of Two Values52762 / 58921
- Maximum Subarray Sum50736 / 52935
- Stick Lengths45354 / 47400
- Missing Coin Sum34333 / 35568
- Collecting Numbers35204 / 37603
- Collecting Numbers II14941 / 18939
- Playlist35129 / 40011
- Towers35234 / 37707
- Traffic Lights27362 / 30554
- Distinct Values Subarrays7481 / 8674
- Distinct Values Subsequences5720 / 6320
- Josephus Problem I21000 / 23079
- Josephus Problem II11423 / 15702
- Nested Ranges Check12297 / 14060
- Nested Ranges Count8262 / 9725
- Room Allocation20603 / 23581
- Factory Machines29676 / 32233
- Tasks and Deadlines23738 / 24235
- Reading Books19207 / 20569
- Sum of Three Values28050 / 30997
- Sum of Four Values17434 / 19353
- Nearest Smaller Values23404 / 24197
- Subarray Sums I31066 / 33075
- Subarray Sums II28240 / 33390
- Subarray Divisibility25582 / 27822
- Distinct Values Subarrays II15491 / 16964
- Array Division24254 / 25506
- Movie Festival II13010 / 15665
- Maximum Subarray Sum II12089 / 14385
Dynamic Programming
- Dice Combinations83479 / 88229
- Minimizing Coins72184 / 77454
- Coin Combinations I65988 / 71281
- Coin Combinations II55839 / 63004
- Removing Digits62106 / 63340
- Grid Paths I58410 / 60030
- Book Shop52312 / 57396
- Array Description38548 / 42713
- Counting Towers23563 / 24956
- Edit Distance38620 / 40742
- Longest Common Subsequence10798 / 11197
- Rectangle Cutting31852 / 34741
- Minimal Grid Path4756 / 8417
- Money Sums37671 / 39076
- Removal Game22718 / 30096
- Two Sets II29625 / 31825
- Mountain Range3297 / 5968
- Increasing Subsequence30288 / 33976
- Projects20995 / 23424
- Elevator Rides13478 / 16882
- Counting Tilings7910 / 8603
- Counting Numbers11232 / 12596
- Increasing Subsequence II4903 / 5708
Graph Algorithms
- Counting Rooms57662 / 60517
- Labyrinth40165 / 47844
- Building Roads50236 / 52038
- Message Route43303 / 44999
- Building Teams40898 / 43063
- Round Trip32358 / 35181
- Monsters22412 / 26267
- Shortest Routes I35600 / 39145
- Shortest Routes II28815 / 32232
- High Score17761 / 24731
- Flight Discount22917 / 26706
- Cycle Finding16211 / 19755
- Flight Routes15724 / 17529
- Round Trip II17806 / 19949
- Course Schedule23628 / 24911
- Longest Flight Route16848 / 20699
- Game Routes18688 / 19962
- Investigation13866 / 14876
- Planets Queries I12064 / 14102
- Planets Queries II4382 / 5525
- Planets Cycles7367 / 8206
- Road Reparation18307 / 19077
- Road Construction20091 / 20733
- Flight Routes Check15994 / 17306
- Planets and Kingdoms12847 / 13360
- Giant Pizza5376 / 5903
- Coin Collector8438 / 9307
- Mail Delivery6931 / 7572
- De Bruijn Sequence3669 / 3837
- Teleporters Path5313 / 6047
- Hamiltonian Flights8036 / 9142
- Knight's Tour3044 / 3676
- Download Speed5323 / 7078
- Police Chase4259 / 4766
- School Dance4672 / 4934
- Distinct Routes3298 / 4293
Range Queries
- Static Range Sum Queries40288 / 42066
- Static Range Minimum Queries27988 / 29962
- Dynamic Range Sum Queries29056 / 30331
- Dynamic Range Minimum Queries26302 / 26930
- Range Xor Queries27053 / 27408
- Range Update Queries21590 / 23125
- Forest Queries22139 / 22933
- Hotel Queries15686 / 16610
- List Removals13002 / 13652
- Salary Queries9843 / 12352
- Prefix Sum Queries8379 / 9045
- Pizzeria Queries6739 / 6981
- Visible Buildings Queries1743 / 1904
- Range Interval Queries1352 / 1817
- Subarray Sum Queries7886 / 8537
- Subarray Sum Queries II1940 / 2006
- Distinct Values Queries7404 / 9073
- Distinct Values Queries II1134 / 1289
- Increasing Array Queries2844 / 3251
- Movie Festival Queries1501 / 1665
- Forest Queries II4698 / 5047
- Range Updates and Sums6426 / 7595
- Polynomial Queries4754 / 5585
- Range Queries and Copies3370 / 3599
- Missing Coin Sum Queries778 / 1014
Tree Algorithms
- Subordinates32973 / 35279
- Tree Matching18781 / 21774
- Tree Diameter26866 / 28459
- Tree Distances I20629 / 22150
- Tree Distances II16834 / 17613
- Company Queries I18776 / 19757
- Company Queries II17579 / 18505
- Distance Queries15898 / 17057
- Counting Paths10004 / 10588
- Subtree Queries11995 / 12771
- Path Queries9645 / 10209
- Path Queries II4017 / 5979
- Distinct Colors9267 / 10196
- Finding a Centroid7488 / 7789
- Fixed-Length Paths I3675 / 4690
- Fixed-Length Paths II1744 / 3132
Mathematics
- Josephus Queries5193 / 6542
- Exponentiation26159 / 27896
- Exponentiation II18322 / 21855
- Counting Divisors23859 / 26907
- Common Divisors15424 / 17847
- Sum of Divisors8671 / 12875
- Divisor Analysis5948 / 7935
- Prime Multiples6891 / 8024
- Counting Coprime Pairs4560 / 5276
- Next Prime2104 / 2413
- Binomial Coefficients11097 / 12285
- Creating Strings II9273 / 9778
- Distributing Apples8840 / 9498
- Christmas Party7263 / 7771
- Permutation Order1009 / 1031
- Permutation Rounds1388 / 1547
- Bracket Sequences I4926 / 5360
- Bracket Sequences II2605 / 2974
- Counting Necklaces2380 / 2574
- Counting Grids1979 / 2103
- Fibonacci Numbers7424 / 9288
- Throwing Dice3879 / 4214
- Graph Paths I3738 / 3999
- Graph Paths II3124 / 3271
- System of Linear Equations507 / 554
- Sum of Four Squares737 / 866
- Triangle Number Sums632 / 767
- Dice Probability3326 / 3582
- Moving Robots1730 / 1827
- Candy Lottery1652 / 3265
- Inversion Probability462 / 2427
- Stick Game3782 / 3873
- Nim Game I5024 / 5207
- Nim Game II3974 / 4131
- Stair Game2712 / 2942
- Grundy's Game1890 / 2474
- Another Game2125 / 2288
String Algorithms
- Word Combinations6383 / 9173
- String Matching12325 / 16424
- Finding Borders9040 / 9872
- Finding Periods6410 / 7254
- Minimal Rotation3117 / 4697
- Longest Palindrome4692 / 6176
- All Palindromes682 / 775
- Required Substring1802 / 2716
- Palindrome Queries2204 / 2570
- Finding Patterns2070 / 2915
- Counting Patterns1958 / 2420
- Pattern Positions1651 / 2004
- Distinct Substrings1861 / 2216
- Distinct Subsequences1164 / 1238
- Repeating Substring2007 / 2327
- String Functions1757 / 1843
- Inverse Suffix Array255 / 301
- String Transform572 / 692
- Substring Order I1265 / 1409
- Substring Order II837 / 1088
- Substring Distribution1174 / 1274
Geometry
- Point Location Test7904 / 8800
- Line Segment Intersection4687 / 5864
- Polygon Area5407 / 5714
- Point in Polygon2977 / 3784
- Polygon Lattice Points2508 / 2591
- Minimum Euclidean Distance2155 / 3056
- Convex Hull3634 / 4333
- Maximum Manhattan Distances644 / 667
- All Manhattan Distances635 / 693
- Intersection Points2126 / 2290
- Line Segments Trace I344 / 358
- Line Segments Trace II284 / 301
- Lines and Queries I398 / 416
- Lines and Queries II342 / 354
- Area of Rectangles1226 / 1371
- Robot Path330 / 611
Advanced Techniques
- Meet in the Middle7174 / 9871
- Hamming Distance3406 / 3724
- Corner Subgrid Check357 / 549
- Corner Subgrid Count2348 / 2636
- Reachable Nodes2422 / 2602
- Reachability Queries1619 / 1904
- Cut and Paste1645 / 1823
- Substring Reversals1432 / 1553
- Reversals and Sums1454 / 1559
- Necessary Roads2111 / 2168
- Necessary Cities1949 / 2039
- Eulerian Subgraphs852 / 896
- Monster Game I1236 / 1374
- Monster Game II1095 / 1172
- Subarray Squares1545 / 1809
- Houses and Schools827 / 989
- Knuth Division1014 / 1144
- Apples and Bananas1157 / 1254
- One Bit Positions904 / 985
- Signal Processing866 / 927
- New Roads Queries2357 / 2846
- Dynamic Connectivity1079 / 1216
- Parcel Delivery828 / 912
- Task Assignment960 / 1034
- Distinct Routes II625 / 712
Sliding Window Problems
- Sliding Window Sum5934 / 6151
- Sliding Window Minimum4436 / 5073
- Sliding Window Xor4336 / 4395
- Sliding Window Or1914 / 3278
- Sliding Window Distinct Values2957 / 3619
- Sliding Window Mode2402 / 2552
- Sliding Window Mex2216 / 2339
- Sliding Window Median14282 / 16300
- Sliding Window Cost9355 / 10785
- Sliding Window Inversions1240 / 1316
- Sliding Window Advertisement235 / 376
Interactive Problems
- Hidden Integer2339 / 2434
- Hidden Permutation997 / 1166
- K-th Highest Score437 / 530
- Permuted Binary Strings547 / 561
- Colored Chairs494 / 521
- Inversion Sorting284 / 317
Bitwise Operations
- Counting Bits5323 / 6878
- Maximum Xor Subarray3170 / 3618
- Maximum Xor Subset1047 / 1142
- Number of Subset Xors928 / 947
- K Subset Xors465 / 552
- All Subarray Xors283 / 467
- Xor Pyramid Peak2150 / 2602
- Xor Pyramid Diagonal330 / 369
- Xor Pyramid Row280 / 331
- SOS Bit Problem2257 / 2398
- And Subset Count444 / 462
Construction Problems
- Inverse Inversions1759 / 1873
- Monotone Subsequences1059 / 1250
- Third Permutation424 / 513
- Permutation Prime Sums429 / 464
- Chess Tournament1253 / 1449
- Distinct Sums Grid135 / 211
- Filling Trominos244 / 440
- Grid Path Construction123 / 440
Advanced Graph Problems
- Nearest Shops731 / 945
- Prüfer Code1592 / 1710
- Tree Traversals1290 / 1421
- Course Schedule II2009 / 2873
- Acyclic Graph Edges2290 / 2427
- Strongly Connected Edges1563 / 1845
- Even Outdegree Edges1424 / 1661
- Graph Girth3560 / 4045
- Fixed Length Walk Queries365 / 406
- Transfer Speeds Sum424 / 438
- MST Edge Check649 / 706
- MST Edge Set Check244 / 277
- MST Edge Cost395 / 412
- Network Breakdown1203 / 1312
- Tree Coin Collecting I347 / 379
- Tree Coin Collecting II188 / 220
- Tree Isomorphism I1131 / 1347
- Tree Isomorphism II929 / 1073
- Flight Route Requests516 / 636
- Critical Cities437 / 674
- Visiting Cities700 / 924
- Graph Coloring231 / 271
- Bus Companies272 / 280
- Split into Two Paths97 / 175
- Network Renovation964 / 1280
- Forbidden Cities873 / 1138
- Creating Offices430 / 561
- New Flight Routes341 / 918
Counting Problems
- Filled Subgrid Count I591 / 664
- Filled Subgrid Count II318 / 390
- All Letter Subgrid Count I174 / 265
- All Letter Subgrid Count II141 / 179
- Border Subgrid Count I93 / 165
- Border Subgrid Count II101 / 118
- Raab Game II107 / 123
- Empty String1730 / 2106
- Permutation Inversions1063 / 1172
- Counting Bishops407 / 454
- Counting Sequences676 / 730
- Grid Paths II782 / 980
- Counting Permutations918 / 1036
- Grid Completion231 / 292
- Counting Reorders250 / 359
- Tournament Graph Distribution107 / 114
- Collecting Numbers Distribution113 / 121
- Functional Graph Distribution252 / 310
Additional Problems I
- Shortest Subsequence3073 / 4048
- Distinct Values Sum673 / 696
- Distinct Values Splits489 / 518
- Swap Game2088 / 2687
- Beautiful Permutation II544 / 828
- Multiplication Table7065 / 7866
- Bubble Sort Rounds I407 / 467
- Bubble Sort Rounds II268 / 304
- Nearest Campsites I181 / 211
- Nearest Campsites II177 / 189
- Advertisement4520 / 4789
- Special Substrings1006 / 1105
- Counting LCM Arrays275 / 301
- Square Subsets224 / 249
- Subarray Sum Constraints400 / 426
- Water Containers Moves173 / 183
- Water Containers Queries209 / 219
- Stack Weights600 / 716
- Maximum Average Subarrays170 / 187
- Subsets with Fixed Average213 / 231
- Two Array Average209 / 234
- Pyramid Array774 / 937
- Permutation Subsequence250 / 258
- Bit Inversions2386 / 2699
- Writing Numbers755 / 815
- Letter Pair Move Game208 / 288
- Maximum Building I2136 / 2228
- Sorting Methods790 / 844
- Cyclic Array1235 / 1405
- List of Sums501 / 650
Additional Problems II
- Bouncing Ball Steps234 / 257
- Bouncing Ball Cycle90 / 128
- Knight Moves Queries119 / 142
- K Subset Sums I189 / 244
- K Subset Sums II107 / 140
- Increasing Array II816 / 932
- Food Division529 / 637
- Swap Round Sorting422 / 520
- Binary Subsequences297 / 432
- School Excursion1415 / 1499
- Coin Grid910 / 1063
- Grid Coloring II138 / 179
- Programmers and Artists514 / 718
- Removing Digits II218 / 475
- Coin Arrangement341 / 454
- Replace with Difference129 / 154
- Grid Puzzle I552 / 607
- Grid Puzzle II528 / 581
- Bit Substrings407 / 493
- Reversal Sorting361 / 437
- Book Shop II1269 / 1445
- GCD Subsets415 / 427
- Minimum Cost Pairs142 / 186
- Same Sum Subsets115 / 218
- Mex Grid Queries867 / 1015
- Maximum Building II457 / 563
- Stick Divisions3901 / 4569
- Stick Difference60 / 253
- Coding Company1542 / 2016
- Two Stacks Sorting182 / 586