General
Introductory Problems
- Weird Algorithm164056 / 171576
- Missing Number141627 / 148264
- Repetitions123196 / 127988
- Increasing Array115940 / 119928
- Permutations101799 / 104804
- Number Spiral72018 / 78309
- Two Knights55269 / 56968
- Two Sets60136 / 64539
- Bit Strings68725 / 72452
- Trailing Zeros63746 / 67716
- Coin Piles56565 / 61720
- Palindrome Reorder52576 / 55433
- Gray Code35554 / 39805
- Tower of Hanoi33025 / 34322
- Creating Strings44364 / 45480
- Apple Division44803 / 50465
- Chessboard and Queens27067 / 27544
- Raab Game I5825 / 6613
- Mex Grid Construction5670 / 5981
- Knight Moves Grid5715 / 5839
- Grid Coloring I4772 / 4938
- Digit Queries19074 / 22042
- String Reorder4329 / 5003
- Grid Path Description10593 / 13695
Sorting and Searching
- Distinct Numbers81114 / 87517
- Apartments60571 / 66955
- Ferris Wheel58119 / 62476
- Concert Tickets46618 / 54063
- Restaurant Customers47422 / 51072
- Movie Festival45868 / 48498
- Sum of Two Values53379 / 59578
- Maximum Subarray Sum51287 / 53501
- Stick Lengths45807 / 47860
- Missing Coin Sum34764 / 36005
- Collecting Numbers35594 / 38005
- Collecting Numbers II15162 / 19185
- Playlist35595 / 40522
- Towers35634 / 38122
- Traffic Lights27677 / 30886
- Distinct Values Subarrays7811 / 9014
- Distinct Values Subsequences5972 / 6587
- Josephus Problem I21291 / 23381
- Josephus Problem II11580 / 15913
- Nested Ranges Check12485 / 14259
- Nested Ranges Count8405 / 9882
- Room Allocation20847 / 23845
- Factory Machines30101 / 32675
- Tasks and Deadlines24025 / 24521
- Reading Books19442 / 20805
- Sum of Three Values28355 / 31318
- Sum of Four Values17659 / 19578
- Nearest Smaller Values23705 / 24506
- Subarray Sums I31455 / 33482
- Subarray Sums II28613 / 33795
- Subarray Divisibility25894 / 28139
- Distinct Values Subarrays II15716 / 17191
- Array Division24598 / 25846
- Movie Festival II13186 / 15862
- Maximum Subarray Sum II12265 / 14576
Dynamic Programming
- Dice Combinations84455 / 89266
- Minimizing Coins72995 / 78305
- Coin Combinations I66734 / 72091
- Coin Combinations II56472 / 63697
- Removing Digits62779 / 64030
- Grid Paths I59075 / 60712
- Book Shop52927 / 58062
- Array Description38974 / 43176
- Counting Towers23848 / 25254
- Edit Distance39032 / 41171
- Longest Common Subsequence11170 / 11581
- Rectangle Cutting32150 / 35052
- Minimal Grid Path4940 / 8680
- Money Sums38034 / 39449
- Removal Game22983 / 30360
- Two Sets II29918 / 32133
- Mountain Range3440 / 6160
- Increasing Subsequence30556 / 34269
- Projects21224 / 23663
- Elevator Rides13631 / 17056
- Counting Tilings8001 / 8702
- Counting Numbers11465 / 12839
- Increasing Subsequence II5015 / 5831
Graph Algorithms
- Counting Rooms58363 / 61243
- Labyrinth40716 / 48434
- Building Roads50877 / 52682
- Message Route43876 / 45582
- Building Teams41433 / 43604
- Round Trip32726 / 35560
- Monsters22728 / 26591
- Shortest Routes I36122 / 39685
- Shortest Routes II29178 / 32618
- High Score18066 / 25073
- Flight Discount23326 / 27141
- Cycle Finding16479 / 20043
- Flight Routes15997 / 17810
- Round Trip II18028 / 20188
- Course Schedule24026 / 25323
- Longest Flight Route17141 / 21019
- Game Routes18924 / 20201
- Investigation14123 / 15148
- Planets Queries I12232 / 14284
- Planets Queries II4453 / 5604
- Planets Cycles7491 / 8339
- Road Reparation18565 / 19333
- Road Construction20436 / 21085
- Flight Routes Check16185 / 17503
- Planets and Kingdoms13087 / 13608
- Giant Pizza5484 / 6014
- Coin Collector8582 / 9463
- Mail Delivery7025 / 7669
- De Bruijn Sequence3722 / 3895
- Teleporters Path5392 / 6129
- Hamiltonian Flights8157 / 9274
- Knight's Tour3096 / 3735
- Download Speed5413 / 7177
- Police Chase4317 / 4829
- School Dance4747 / 5012
- Distinct Routes3346 / 4349
Range Queries
- Static Range Sum Queries40812 / 42637
- Static Range Minimum Queries28293 / 30286
- Dynamic Range Sum Queries29377 / 30661
- Dynamic Range Minimum Queries26581 / 27211
- Range Xor Queries27370 / 27743
- Range Update Queries21850 / 23394
- Forest Queries22401 / 23199
- Hotel Queries15867 / 16797
- List Removals13171 / 13827
- Salary Queries10007 / 12528
- Prefix Sum Queries8504 / 9173
- Pizzeria Queries6829 / 7074
- Visible Buildings Queries1816 / 1979
- Range Interval Queries1409 / 1890
- Subarray Sum Queries7977 / 8630
- Subarray Sum Queries II2024 / 2093
- Distinct Values Queries7517 / 9191
- Distinct Values Queries II1175 / 1334
- Increasing Array Queries2885 / 3296
- Movie Festival Queries1539 / 1704
- Forest Queries II4758 / 5107
- Range Updates and Sums6531 / 7706
- Polynomial Queries4824 / 5662
- Range Queries and Copies3424 / 3654
- Missing Coin Sum Queries802 / 1044
Tree Algorithms
- Subordinates33376 / 35703
- Tree Matching19011 / 22029
- Tree Diameter27214 / 28816
- Tree Distances I20880 / 22415
- Tree Distances II17027 / 17812
- Company Queries I18989 / 19981
- Company Queries II17765 / 18692
- Distance Queries16073 / 17236
- Counting Paths10099 / 10686
- Subtree Queries12125 / 12900
- Path Queries9750 / 10312
- Path Queries II4077 / 6053
- Distinct Colors9402 / 10335
- Finding a Centroid7592 / 7896
- Fixed-Length Paths I3750 / 4771
- Fixed-Length Paths II1785 / 3196
Mathematics
- Josephus Queries5257 / 6623
- Exponentiation26424 / 28169
- Exponentiation II18504 / 22065
- Counting Divisors24128 / 27204
- Common Divisors15601 / 18042
- Sum of Divisors8791 / 13029
- Divisor Analysis6029 / 8026
- Prime Multiples7007 / 8149
- Counting Coprime Pairs4628 / 5352
- Next Prime2186 / 2503
- Binomial Coefficients11254 / 12450
- Creating Strings II9381 / 9888
- Distributing Apples8950 / 9613
- Christmas Party7350 / 7856
- Permutation Order1041 / 1064
- Permutation Rounds1454 / 1618
- Bracket Sequences I4967 / 5401
- Bracket Sequences II2626 / 2997
- Counting Necklaces2411 / 2605
- Counting Grids2011 / 2135
- Fibonacci Numbers7492 / 9362
- Throwing Dice3912 / 4247
- Graph Paths I3773 / 4036
- Graph Paths II3153 / 3302
- System of Linear Equations527 / 574
- Sum of Four Squares766 / 896
- Triangle Number Sums656 / 792
- Dice Probability3348 / 3603
- Moving Robots1743 / 1840
- Candy Lottery1679 / 3295
- Inversion Probability484 / 2450
- Stick Game3821 / 3911
- Nim Game I5100 / 5284
- Nim Game II4028 / 4185
- Stair Game2751 / 2984
- Grundy's Game1908 / 2497
- Another Game2157 / 2321
String Algorithms
- Word Combinations6498 / 9299
- String Matching12491 / 16621
- Finding Borders9160 / 10002
- Finding Periods6504 / 7353
- Minimal Rotation3184 / 4770
- Longest Palindrome4774 / 6265
- All Palindromes719 / 816
- Required Substring1848 / 2772
- Palindrome Queries2248 / 2615
- Finding Patterns2120 / 2967
- Counting Patterns2008 / 2473
- Pattern Positions1691 / 2049
- Distinct Substrings1907 / 2266
- Distinct Subsequences1211 / 1285
- Repeating Substring2058 / 2375
- String Functions1802 / 1887
- Inverse Suffix Array279 / 326
- String Transform599 / 718
- Substring Order I1312 / 1456
- Substring Order II872 / 1129
- Substring Distribution1213 / 1315
Geometry
- Point Location Test7988 / 8893
- Line Segment Intersection4741 / 5924
- Polygon Area5466 / 5772
- Point in Polygon3022 / 3834
- Polygon Lattice Points2539 / 2622
- Minimum Euclidean Distance2191 / 3094
- Convex Hull3670 / 4369
- Maximum Manhattan Distances669 / 692
- All Manhattan Distances668 / 726
- Intersection Points2162 / 2332
- Line Segments Trace I368 / 382
- Line Segments Trace II306 / 324
- Lines and Queries I423 / 441
- Lines and Queries II364 / 376
- Area of Rectangles1249 / 1394
- Robot Path334 / 621
Advanced Techniques
- Meet in the Middle7263 / 9976
- Hamming Distance3429 / 3752
- Corner Subgrid Check372 / 568
- Corner Subgrid Count2370 / 2666
- Reachable Nodes2448 / 2631
- Reachability Queries1637 / 1924
- Cut and Paste1672 / 1851
- Substring Reversals1458 / 1579
- Reversals and Sums1482 / 1588
- Necessary Roads2144 / 2200
- Necessary Cities1995 / 2086
- Eulerian Subgraphs861 / 905
- Monster Game I1266 / 1405
- Monster Game II1124 / 1201
- Subarray Squares1577 / 1842
- Houses and Schools854 / 1020
- Knuth Division1031 / 1161
- Apples and Bananas1182 / 1284
- One Bit Positions915 / 997
- Signal Processing881 / 943
- New Roads Queries2406 / 2908
- Dynamic Connectivity1103 / 1240
- Parcel Delivery848 / 932
- Task Assignment984 / 1058
- Distinct Routes II644 / 730
Sliding Window Problems
- Sliding Window Sum6154 / 6382
- Sliding Window Minimum4586 / 5239
- Sliding Window Xor4507 / 4571
- Sliding Window Or1992 / 3391
- Sliding Window Distinct Values3088 / 3755
- Sliding Window Mode2480 / 2642
- Sliding Window Mex2313 / 2443
- Sliding Window Median14381 / 16403
- Sliding Window Cost9408 / 10846
- Sliding Window Inversions1287 / 1364
- Sliding Window Advertisement245 / 391
Interactive Problems
- Hidden Integer2436 / 2535
- Hidden Permutation1041 / 1218
- K-th Highest Score461 / 560
- Permuted Binary Strings564 / 578
- Colored Chairs516 / 544
- Inversion Sorting293 / 328
Bitwise Operations
- Counting Bits5427 / 7019
- Maximum Xor Subarray3234 / 3695
- Maximum Xor Subset1087 / 1189
- Number of Subset Xors954 / 974
- K Subset Xors482 / 575
- All Subarray Xors295 / 481
- Xor Pyramid Peak2181 / 2634
- Xor Pyramid Diagonal341 / 381
- Xor Pyramid Row294 / 345
- SOS Bit Problem2296 / 2437
- And Subset Count459 / 477
Construction Problems
- Inverse Inversions1791 / 1907
- Monotone Subsequences1083 / 1278
- Third Permutation440 / 531
- Permutation Prime Sums441 / 476
- Chess Tournament1265 / 1465
- Distinct Sums Grid140 / 217
- Filling Trominos247 / 448
- Grid Path Construction125 / 445
Advanced Graph Problems
- Nearest Shops761 / 982
- Prüfer Code1607 / 1725
- Tree Traversals1303 / 1434
- Course Schedule II2050 / 2925
- Acyclic Graph Edges2313 / 2448
- Strongly Connected Edges1592 / 1873
- Even Outdegree Edges1446 / 1682
- Graph Girth3612 / 4097
- Fixed Length Walk Queries379 / 420
- Transfer Speeds Sum443 / 457
- MST Edge Check683 / 742
- MST Edge Set Check260 / 293
- MST Edge Cost414 / 433
- Network Breakdown1229 / 1337
- Tree Coin Collecting I366 / 398
- Tree Coin Collecting II200 / 233
- Tree Isomorphism I1142 / 1356
- Tree Isomorphism II939 / 1082
- Flight Route Requests525 / 645
- Critical Cities449 / 688
- Visiting Cities714 / 939
- Graph Coloring242 / 284
- Bus Companies286 / 293
- Split into Two Paths104 / 188
- Network Renovation975 / 1292
- Forbidden Cities885 / 1155
- Creating Offices437 / 572
- New Flight Routes348 / 926
Counting Problems
- Filled Subgrid Count I619 / 695
- Filled Subgrid Count II335 / 413
- All Letter Subgrid Count I188 / 281
- All Letter Subgrid Count II148 / 189
- Border Subgrid Count I103 / 179
- Border Subgrid Count II111 / 130
- Raab Game II112 / 129
- Empty String1771 / 2149
- Permutation Inversions1072 / 1183
- Counting Bishops414 / 460
- Counting Sequences703 / 757
- Grid Paths II800 / 1001
- Counting Permutations932 / 1051
- Grid Completion235 / 299
- Counting Reorders259 / 368
- Tournament Graph Distribution113 / 120
- Collecting Numbers Distribution122 / 130
- Functional Graph Distribution254 / 314
Additional Problems I
- Shortest Subsequence3100 / 4079
- Distinct Values Sum705 / 729
- Distinct Values Splits509 / 540
- Swap Game2109 / 2711
- Beautiful Permutation II576 / 873
- Multiplication Table7159 / 7970
- Bubble Sort Rounds I433 / 493
- Bubble Sort Rounds II290 / 326
- Nearest Campsites I191 / 223
- Nearest Campsites II188 / 201
- Advertisement4578 / 4848
- Special Substrings1016 / 1115
- Counting LCM Arrays287 / 313
- Square Subsets233 / 258
- Subarray Sum Constraints436 / 464
- Water Containers Moves186 / 196
- Water Containers Queries220 / 231
- Stack Weights614 / 732
- Maximum Average Subarrays180 / 198
- Subsets with Fixed Average221 / 240
- Two Array Average220 / 247
- Pyramid Array791 / 956
- Permutation Subsequence271 / 279
- Bit Inversions2417 / 2731
- Writing Numbers765 / 826
- Letter Pair Move Game211 / 291
- Maximum Building I2161 / 2253
- Sorting Methods799 / 853
- Cyclic Array1258 / 1430
- List of Sums509 / 659
Additional Problems II
- Bouncing Ball Steps244 / 270
- Bouncing Ball Cycle96 / 134
- Knight Moves Queries124 / 148
- K Subset Sums I198 / 254
- K Subset Sums II115 / 147
- Increasing Array II843 / 960
- Food Division539 / 647
- Swap Round Sorting428 / 528
- Binary Subsequences297 / 433
- School Excursion1437 / 1520
- Coin Grid930 / 1085
- Grid Coloring II144 / 187
- Programmers and Artists525 / 735
- Removing Digits II221 / 481
- Coin Arrangement344 / 461
- Replace with Difference135 / 161
- Grid Puzzle I564 / 617
- Grid Puzzle II545 / 597
- Bit Substrings411 / 498
- Reversal Sorting367 / 445
- Book Shop II1296 / 1474
- GCD Subsets430 / 442
- Minimum Cost Pairs150 / 195
- Same Sum Subsets119 / 235
- Mex Grid Queries879 / 1029
- Maximum Building II461 / 568
- Stick Divisions3926 / 4595
- Stick Difference66 / 267
- Coding Company1560 / 2041
- Two Stacks Sorting185 / 594