General
Introductory Problems
- Weird Algorithm163395 / 170892
- Missing Number141035 / 147655
- Repetitions122663 / 127448
- Increasing Array115471 / 119454
- Permutations101383 / 104378
- Number Spiral71728 / 78004
- Two Knights55029 / 56725
- Two Sets59884 / 64276
- Bit Strings68457 / 72170
- Trailing Zeros63531 / 67490
- Coin Piles56354 / 61497
- Palindrome Reorder52412 / 55257
- Gray Code35414 / 39659
- Tower of Hanoi32890 / 34192
- Creating Strings44210 / 45322
- Apple Division44549 / 50191
- Chessboard and Queens26942 / 27419
- Raab Game I5729 / 6513
- Mex Grid Construction5579 / 5888
- Knight Moves Grid5603 / 5727
- Grid Coloring I4688 / 4851
- Digit Queries18985 / 21949
- String Reorder4250 / 4920
- Grid Path Description10537 / 13632
Sorting and Searching
- Distinct Numbers80784 / 87174
- Apartments60336 / 66707
- Ferris Wheel57905 / 62253
- Concert Tickets46436 / 53871
- Restaurant Customers47243 / 50884
- Movie Festival45697 / 48318
- Sum of Two Values53184 / 59367
- Maximum Subarray Sum51100 / 53307
- Stick Lengths45653 / 47700
- Missing Coin Sum34611 / 35851
- Collecting Numbers35462 / 37870
- Collecting Numbers II15075 / 19091
- Playlist35387 / 40288
- Towers35490 / 37975
- Traffic Lights27567 / 30769
- Distinct Values Subarrays7703 / 8902
- Distinct Values Subsequences5877 / 6484
- Josephus Problem I21188 / 23279
- Josephus Problem II11511 / 15831
- Nested Ranges Check12411 / 14182
- Nested Ranges Count8352 / 9821
- Room Allocation20765 / 23750
- Factory Machines29944 / 32515
- Tasks and Deadlines23927 / 24424
- Reading Books19359 / 20723
- Sum of Three Values28267 / 31226
- Sum of Four Values17581 / 19502
- Nearest Smaller Values23604 / 24401
- Subarray Sums I31319 / 33342
- Subarray Sums II28484 / 33654
- Subarray Divisibility25785 / 28026
- Distinct Values Subarrays II15636 / 17110
- Array Division24468 / 25717
- Movie Festival II13126 / 15795
- Maximum Subarray Sum II12199 / 14505
Dynamic Programming
- Dice Combinations84098 / 88869
- Minimizing Coins72734 / 78026
- Coin Combinations I66479 / 71806
- Coin Combinations II56266 / 63461
- Removing Digits62541 / 63785
- Grid Paths I58831 / 60457
- Book Shop52710 / 57818
- Array Description38833 / 43023
- Counting Towers23757 / 25159
- Edit Distance38881 / 41023
- Longest Common Subsequence11052 / 11457
- Rectangle Cutting32059 / 34953
- Minimal Grid Path4868 / 8592
- Money Sums37909 / 39323
- Removal Game22887 / 30264
- Two Sets II29803 / 32015
- Mountain Range3382 / 6095
- Increasing Subsequence30442 / 34150
- Projects21136 / 23573
- Elevator Rides13574 / 16989
- Counting Tilings7968 / 8667
- Counting Numbers11390 / 12759
- Increasing Subsequence II4976 / 5787
Graph Algorithms
- Counting Rooms58120 / 60988
- Labyrinth40527 / 48235
- Building Roads50662 / 52467
- Message Route43682 / 45387
- Building Teams41253 / 43425
- Round Trip32607 / 35436
- Monsters22623 / 26485
- Shortest Routes I35968 / 39523
- Shortest Routes II29063 / 32490
- High Score17967 / 24961
- Flight Discount23206 / 27012
- Cycle Finding16404 / 19966
- Flight Routes15908 / 17719
- Round Trip II17956 / 20106
- Course Schedule23901 / 25193
- Longest Flight Route17030 / 20898
- Game Routes18844 / 20119
- Investigation14036 / 15051
- Planets Queries I12164 / 14212
- Planets Queries II4423 / 5571
- Planets Cycles7434 / 8278
- Road Reparation18471 / 19241
- Road Construction20323 / 20972
- Flight Routes Check16126 / 17443
- Planets and Kingdoms12973 / 13487
- Giant Pizza5441 / 5968
- Coin Collector8523 / 9400
- Mail Delivery6997 / 7641
- De Bruijn Sequence3702 / 3872
- Teleporters Path5364 / 6099
- Hamiltonian Flights8110 / 9228
- Knight's Tour3079 / 3717
- Download Speed5374 / 7133
- Police Chase4298 / 4806
- School Dance4721 / 4985
- Distinct Routes3327 / 4324
Range Queries
- Static Range Sum Queries40660 / 42478
- Static Range Minimum Queries28188 / 30179
- Dynamic Range Sum Queries29259 / 30544
- Dynamic Range Minimum Queries26479 / 27109
- Range Xor Queries27240 / 27601
- Range Update Queries21758 / 23294
- Forest Queries22293 / 23091
- Hotel Queries15812 / 16741
- List Removals13106 / 13759
- Salary Queries9940 / 12454
- Prefix Sum Queries8454 / 9124
- Pizzeria Queries6798 / 7042
- Visible Buildings Queries1792 / 1953
- Range Interval Queries1382 / 1860
- Subarray Sum Queries7944 / 8596
- Subarray Sum Queries II1998 / 2066
- Distinct Values Queries7474 / 9145
- Distinct Values Queries II1158 / 1315
- Increasing Array Queries2873 / 3282
- Movie Festival Queries1525 / 1690
- Forest Queries II4736 / 5085
- Range Updates and Sums6478 / 7648
- Polynomial Queries4794 / 5630
- Range Queries and Copies3404 / 3634
- Missing Coin Sum Queries790 / 1030
Tree Algorithms
- Subordinates33224 / 35546
- Tree Matching18925 / 21934
- Tree Diameter27108 / 28711
- Tree Distances I20798 / 22331
- Tree Distances II16963 / 17744
- Company Queries I18920 / 19906
- Company Queries II17705 / 18635
- Distance Queries16013 / 17171
- Counting Paths10067 / 10655
- Subtree Queries12073 / 12850
- Path Queries9710 / 10272
- Path Queries II4057 / 6029
- Distinct Colors9354 / 10284
- Finding a Centroid7556 / 7859
- Fixed-Length Paths I3722 / 4741
- Fixed-Length Paths II1767 / 3170
Mathematics
- Josephus Queries5238 / 6594
- Exponentiation26336 / 28078
- Exponentiation II18454 / 22003
- Counting Divisors24045 / 27113
- Common Divisors15541 / 17971
- Sum of Divisors8757 / 12980
- Divisor Analysis6010 / 8005
- Prime Multiples6968 / 8109
- Counting Coprime Pairs4601 / 5323
- Next Prime2155 / 2470
- Binomial Coefficients11211 / 12404
- Creating Strings II9344 / 9852
- Distributing Apples8905 / 9567
- Christmas Party7324 / 7832
- Permutation Order1030 / 1053
- Permutation Rounds1428 / 1592
- Bracket Sequences I4951 / 5385
- Bracket Sequences II2616 / 2987
- Counting Necklaces2402 / 2596
- Counting Grids1999 / 2123
- Fibonacci Numbers7469 / 9337
- Throwing Dice3902 / 4237
- Graph Paths I3762 / 4024
- Graph Paths II3144 / 3292
- System of Linear Equations516 / 563
- Sum of Four Squares756 / 886
- Triangle Number Sums646 / 785
- Dice Probability3338 / 3594
- Moving Robots1736 / 1833
- Candy Lottery1669 / 3285
- Inversion Probability472 / 2439
- Stick Game3804 / 3894
- Nim Game I5077 / 5260
- Nim Game II4010 / 4167
- Stair Game2725 / 2956
- Grundy's Game1896 / 2482
- Another Game2134 / 2296
String Algorithms
- Word Combinations6436 / 9235
- String Matching12430 / 16549
- Finding Borders9111 / 9951
- Finding Periods6466 / 7312
- Minimal Rotation3150 / 4731
- Longest Palindrome4734 / 6226
- All Palindromes698 / 796
- Required Substring1824 / 2742
- Palindrome Queries2221 / 2589
- Finding Patterns2096 / 2943
- Counting Patterns1982 / 2445
- Pattern Positions1667 / 2025
- Distinct Substrings1881 / 2238
- Distinct Subsequences1181 / 1255
- Repeating Substring2036 / 2354
- String Functions1777 / 1862
- Inverse Suffix Array265 / 312
- String Transform579 / 700
- Substring Order I1286 / 1430
- Substring Order II850 / 1106
- Substring Distribution1187 / 1289
Geometry
- Point Location Test7960 / 8865
- Line Segment Intersection4718 / 5901
- Polygon Area5440 / 5746
- Point in Polygon3004 / 3814
- Polygon Lattice Points2528 / 2611
- Minimum Euclidean Distance2177 / 3081
- Convex Hull3653 / 4354
- Maximum Manhattan Distances659 / 682
- All Manhattan Distances652 / 711
- Intersection Points2151 / 2320
- Line Segments Trace I358 / 372
- Line Segments Trace II296 / 313
- Lines and Queries I410 / 428
- Lines and Queries II355 / 367
- Area of Rectangles1241 / 1386
- Robot Path332 / 617
Advanced Techniques
- Meet in the Middle7227 / 9940
- Hamming Distance3419 / 3738
- Corner Subgrid Check365 / 558
- Corner Subgrid Count2363 / 2658
- Reachable Nodes2435 / 2617
- Reachability Queries1627 / 1913
- Cut and Paste1661 / 1840
- Substring Reversals1449 / 1571
- Reversals and Sums1469 / 1574
- Necessary Roads2131 / 2187
- Necessary Cities1982 / 2073
- Eulerian Subgraphs859 / 903
- Monster Game I1250 / 1389
- Monster Game II1108 / 1185
- Subarray Squares1567 / 1832
- Houses and Schools843 / 1007
- Knuth Division1025 / 1155
- Apples and Bananas1172 / 1270
- One Bit Positions912 / 994
- Signal Processing874 / 935
- New Roads Queries2375 / 2872
- Dynamic Connectivity1093 / 1229
- Parcel Delivery840 / 924
- Task Assignment974 / 1048
- Distinct Routes II635 / 722
Sliding Window Problems
- Sliding Window Sum6078 / 6304
- Sliding Window Minimum4534 / 5181
- Sliding Window Xor4455 / 4517
- Sliding Window Or1968 / 3357
- Sliding Window Distinct Values3045 / 3712
- Sliding Window Mode2462 / 2619
- Sliding Window Mex2270 / 2398
- Sliding Window Median14346 / 16369
- Sliding Window Cost9388 / 10823
- Sliding Window Inversions1274 / 1351
- Sliding Window Advertisement243 / 389
Interactive Problems
- Hidden Integer2402 / 2500
- Hidden Permutation1026 / 1203
- K-th Highest Score452 / 549
- Permuted Binary Strings558 / 573
- Colored Chairs506 / 535
- Inversion Sorting287 / 321
Bitwise Operations
- Counting Bits5389 / 6966
- Maximum Xor Subarray3204 / 3658
- Maximum Xor Subset1074 / 1173
- Number of Subset Xors947 / 966
- K Subset Xors477 / 568
- All Subarray Xors292 / 479
- Xor Pyramid Peak2170 / 2622
- Xor Pyramid Diagonal337 / 377
- Xor Pyramid Row289 / 340
- SOS Bit Problem2279 / 2420
- And Subset Count457 / 475
Construction Problems
- Inverse Inversions1780 / 1898
- Monotone Subsequences1073 / 1266
- Third Permutation432 / 523
- Permutation Prime Sums436 / 471
- Chess Tournament1261 / 1460
- Distinct Sums Grid139 / 214
- Filling Trominos246 / 446
- Grid Path Construction124 / 442
Advanced Graph Problems
- Nearest Shops751 / 969
- Prüfer Code1599 / 1717
- Tree Traversals1298 / 1429
- Course Schedule II2038 / 2913
- Acyclic Graph Edges2308 / 2444
- Strongly Connected Edges1584 / 1868
- Even Outdegree Edges1441 / 1678
- Graph Girth3593 / 4078
- Fixed Length Walk Queries373 / 414
- Transfer Speeds Sum438 / 452
- MST Edge Check674 / 733
- MST Edge Set Check255 / 288
- MST Edge Cost409 / 427
- Network Breakdown1224 / 1332
- Tree Coin Collecting I363 / 395
- Tree Coin Collecting II194 / 227
- Tree Isomorphism I1140 / 1354
- Tree Isomorphism II937 / 1080
- Flight Route Requests521 / 641
- Critical Cities444 / 682
- Visiting Cities709 / 933
- Graph Coloring238 / 278
- Bus Companies279 / 287
- Split into Two Paths100 / 184
- Network Renovation968 / 1286
- Forbidden Cities880 / 1148
- Creating Offices437 / 570
- New Flight Routes344 / 924
Counting Problems
- Filled Subgrid Count I612 / 686
- Filled Subgrid Count II330 / 407
- All Letter Subgrid Count I184 / 275
- All Letter Subgrid Count II145 / 185
- Border Subgrid Count I97 / 168
- Border Subgrid Count II106 / 124
- Raab Game II111 / 127
- Empty String1752 / 2130
- Permutation Inversions1068 / 1179
- Counting Bishops412 / 459
- Counting Sequences695 / 749
- Grid Paths II791 / 990
- Counting Permutations924 / 1043
- Grid Completion232 / 296
- Counting Reorders256 / 366
- Tournament Graph Distribution110 / 117
- Collecting Numbers Distribution118 / 126
- Functional Graph Distribution253 / 312
Additional Problems I
- Shortest Subsequence3088 / 4067
- Distinct Values Sum698 / 722
- Distinct Values Splits502 / 533
- Swap Game2105 / 2707
- Beautiful Permutation II563 / 853
- Multiplication Table7122 / 7932
- Bubble Sort Rounds I426 / 486
- Bubble Sort Rounds II282 / 318
- Nearest Campsites I187 / 217
- Nearest Campsites II183 / 195
- Advertisement4554 / 4824
- Special Substrings1012 / 1111
- Counting LCM Arrays280 / 306
- Square Subsets231 / 256
- Subarray Sum Constraints426 / 454
- Water Containers Moves183 / 193
- Water Containers Queries217 / 228
- Stack Weights607 / 724
- Maximum Average Subarrays178 / 196
- Subsets with Fixed Average221 / 239
- Two Array Average218 / 244
- Pyramid Array786 / 951
- Permutation Subsequence264 / 272
- Bit Inversions2406 / 2720
- Writing Numbers761 / 822
- Letter Pair Move Game209 / 288
- Maximum Building I2153 / 2245
- Sorting Methods795 / 849
- Cyclic Array1246 / 1418
- List of Sums506 / 656
Additional Problems II
- Bouncing Ball Steps239 / 264
- Bouncing Ball Cycle94 / 133
- Knight Moves Queries121 / 145
- K Subset Sums I195 / 250
- K Subset Sums II110 / 144
- Increasing Array II826 / 943
- Food Division539 / 646
- Swap Round Sorting426 / 525
- Binary Subsequences297 / 433
- School Excursion1433 / 1516
- Coin Grid922 / 1076
- Grid Coloring II143 / 185
- Programmers and Artists519 / 726
- Removing Digits II219 / 478
- Coin Arrangement343 / 456
- Replace with Difference131 / 156
- Grid Puzzle I559 / 613
- Grid Puzzle II539 / 591
- Bit Substrings411 / 497
- Reversal Sorting365 / 441
- Book Shop II1284 / 1462
- GCD Subsets422 / 434
- Minimum Cost Pairs146 / 189
- Same Sum Subsets116 / 223
- Mex Grid Queries873 / 1022
- Maximum Building II461 / 568
- Stick Divisions3918 / 4586
- Stick Difference62 / 262
- Coding Company1557 / 2035
- Two Stacks Sorting184 / 587