General
Introductory Problems
- Weird Algorithm165203 / 172748
- Missing Number142628 / 149286
- Repetitions124055 / 128860
- Increasing Array116768 / 120765
- Permutations102497 / 105517
- Number Spiral72548 / 78859
- Two Knights55728 / 57432
- Two Sets60634 / 65052
- Bit Strings69281 / 73028
- Trailing Zeros64273 / 68263
- Coin Piles57053 / 62222
- Palindrome Reorder53034 / 55901
- Gray Code35897 / 40172
- Tower of Hanoi33369 / 34676
- Creating Strings44743 / 45865
- Apple Division45186 / 50865
- Chessboard and Queens27346 / 27825
- Raab Game I6034 / 6831
- Mex Grid Construction5871 / 6185
- Knight Moves Grid5919 / 6047
- Grid Coloring I4947 / 5120
- Digit Queries19251 / 22224
- String Reorder4487 / 5172
- Grid Path Description10712 / 13827
Sorting and Searching
- Distinct Numbers81692 / 88112
- Apartments61050 / 67449
- Ferris Wheel58597 / 62957
- Concert Tickets47028 / 54510
- Restaurant Customers47807 / 51470
- Movie Festival46268 / 48908
- Sum of Two Values53868 / 60088
- Maximum Subarray Sum51666 / 53887
- Stick Lengths46148 / 48203
- Missing Coin Sum35055 / 36296
- Collecting Numbers35898 / 38319
- Collecting Numbers II15338 / 19383
- Playlist35875 / 40826
- Towers35924 / 38414
- Traffic Lights27888 / 31108
- Distinct Values Subarrays8032 / 9239
- Distinct Values Subsequences6162 / 6784
- Josephus Problem I21494 / 23588
- Josephus Problem II11707 / 16072
- Nested Ranges Check12625 / 14406
- Nested Ranges Count8500 / 9987
- Room Allocation21015 / 24025
- Factory Machines30371 / 32946
- Tasks and Deadlines24218 / 24716
- Reading Books19615 / 20978
- Sum of Three Values28640 / 31619
- Sum of Four Values17815 / 19741
- Nearest Smaller Values23912 / 24717
- Subarray Sums I31737 / 33773
- Subarray Sums II28872 / 34070
- Subarray Divisibility26118 / 28363
- Distinct Values Subarrays II15869 / 17350
- Array Division24788 / 26050
- Movie Festival II13314 / 16001
- Maximum Subarray Sum II12381 / 14702
Dynamic Programming
- Dice Combinations85083 / 89911
- Minimizing Coins73527 / 78859
- Coin Combinations I67221 / 72603
- Coin Combinations II56884 / 64134
- Removing Digits63244 / 64504
- Grid Paths I59513 / 61152
- Book Shop53332 / 58488
- Array Description39267 / 43490
- Counting Towers24066 / 25481
- Edit Distance39336 / 41479
- Longest Common Subsequence11457 / 11875
- Rectangle Cutting32383 / 35300
- Minimal Grid Path5095 / 8912
- Money Sums38300 / 39721
- Removal Game23178 / 30558
- Two Sets II30119 / 32343
- Mountain Range3569 / 6332
- Increasing Subsequence30766 / 34502
- Projects21400 / 23852
- Elevator Rides13759 / 17207
- Counting Tilings8086 / 8790
- Counting Numbers11615 / 12993
- Increasing Subsequence II5103 / 5936
Graph Algorithms
- Counting Rooms58820 / 61718
- Labyrinth41095 / 48826
- Building Roads51274 / 53082
- Message Route44269 / 45978
- Building Teams41783 / 43965
- Round Trip32994 / 35839
- Monsters22960 / 26835
- Shortest Routes I36455 / 40019
- Shortest Routes II29426 / 32872
- High Score18300 / 25326
- Flight Discount23582 / 27417
- Cycle Finding16639 / 20214
- Flight Routes16134 / 17958
- Round Trip II18180 / 20344
- Course Schedule24220 / 25521
- Longest Flight Route17329 / 21215
- Game Routes19109 / 20389
- Investigation14255 / 15283
- Planets Queries I12352 / 14406
- Planets Queries II4512 / 5667
- Planets Cycles7568 / 8424
- Road Reparation18726 / 19499
- Road Construction20627 / 21281
- Flight Routes Check16309 / 17629
- Planets and Kingdoms13221 / 13743
- Giant Pizza5551 / 6082
- Coin Collector8684 / 9570
- Mail Delivery7083 / 7731
- De Bruijn Sequence3753 / 3926
- Teleporters Path5438 / 6177
- Hamiltonian Flights8231 / 9350
- Knight's Tour3134 / 3775
- Download Speed5488 / 7260
- Police Chase4374 / 4886
- School Dance4803 / 5070
- Distinct Routes3393 / 4402
Range Queries
- Static Range Sum Queries41127 / 42968
- Static Range Minimum Queries28481 / 30490
- Dynamic Range Sum Queries29542 / 30832
- Dynamic Range Minimum Queries26729 / 27364
- Range Xor Queries27518 / 27892
- Range Update Queries21980 / 23524
- Forest Queries22551 / 23347
- Hotel Queries15966 / 16900
- List Removals13256 / 13913
- Salary Queries10084 / 12613
- Prefix Sum Queries8569 / 9238
- Pizzeria Queries6891 / 7137
- Visible Buildings Queries1853 / 2018
- Range Interval Queries1441 / 1927
- Subarray Sum Queries8013 / 8668
- Subarray Sum Queries II2060 / 2128
- Distinct Values Queries7588 / 9261
- Distinct Values Queries II1202 / 1362
- Increasing Array Queries2914 / 3323
- Movie Festival Queries1567 / 1731
- Forest Queries II4793 / 5141
- Range Updates and Sums6588 / 7764
- Polynomial Queries4871 / 5716
- Range Queries and Copies3475 / 3704
- Missing Coin Sum Queries817 / 1064
Tree Algorithms
- Subordinates33630 / 35975
- Tree Matching19151 / 22185
- Tree Diameter27415 / 29021
- Tree Distances I21035 / 22581
- Tree Distances II17149 / 17937
- Company Queries I19113 / 20115
- Company Queries II17875 / 18805
- Distance Queries16178 / 17346
- Counting Paths10180 / 10769
- Subtree Queries12207 / 12985
- Path Queries9822 / 10387
- Path Queries II4119 / 6104
- Distinct Colors9476 / 10409
- Finding a Centroid7667 / 7974
- Fixed-Length Paths I3796 / 4818
- Fixed-Length Paths II1809 / 3229
Mathematics
- Josephus Queries5316 / 6686
- Exponentiation26604 / 28359
- Exponentiation II18597 / 22168
- Counting Divisors24275 / 27362
- Common Divisors15694 / 18144
- Sum of Divisors8853 / 13106
- Divisor Analysis6072 / 8087
- Prime Multiples7045 / 8193
- Counting Coprime Pairs4653 / 5375
- Next Prime2227 / 2547
- Binomial Coefficients11333 / 12538
- Creating Strings II9441 / 9952
- Distributing Apples9000 / 9667
- Christmas Party7403 / 7915
- Permutation Order1067 / 1091
- Permutation Rounds1494 / 1660
- Bracket Sequences I5004 / 5440
- Bracket Sequences II2648 / 3024
- Counting Necklaces2427 / 2622
- Counting Grids2025 / 2149
- Fibonacci Numbers7541 / 9419
- Throwing Dice3941 / 4278
- Graph Paths I3799 / 4061
- Graph Paths II3177 / 3325
- System of Linear Equations539 / 583
- Sum of Four Squares775 / 905
- Triangle Number Sums667 / 808
- Dice Probability3368 / 3623
- Moving Robots1755 / 1852
- Candy Lottery1706 / 3320
- Inversion Probability495 / 2479
- Stick Game3850 / 3940
- Nim Game I5135 / 5321
- Nim Game II4055 / 4213
- Stair Game2765 / 2998
- Grundy's Game1920 / 2511
- Another Game2171 / 2335
String Algorithms
- Word Combinations6569 / 9385
- String Matching12603 / 16751
- Finding Borders9249 / 10096
- Finding Periods6564 / 7418
- Minimal Rotation3228 / 4816
- Longest Palindrome4826 / 6320
- All Palindromes748 / 845
- Required Substring1872 / 2801
- Palindrome Queries2281 / 2646
- Finding Patterns2156 / 3005
- Counting Patterns2046 / 2514
- Pattern Positions1720 / 2079
- Distinct Substrings1935 / 2298
- Distinct Subsequences1229 / 1303
- Repeating Substring2092 / 2411
- String Functions1824 / 1909
- Inverse Suffix Array297 / 344
- String Transform612 / 733
- Substring Order I1332 / 1477
- Substring Order II892 / 1147
- Substring Distribution1232 / 1333
Geometry
- Point Location Test8060 / 8966
- Line Segment Intersection4777 / 5967
- Polygon Area5505 / 5811
- Point in Polygon3052 / 3867
- Polygon Lattice Points2559 / 2644
- Minimum Euclidean Distance2204 / 3110
- Convex Hull3702 / 4400
- Maximum Manhattan Distances678 / 701
- All Manhattan Distances678 / 737
- Intersection Points2177 / 2349
- Line Segments Trace I378 / 390
- Line Segments Trace II314 / 331
- Lines and Queries I428 / 446
- Lines and Queries II374 / 385
- Area of Rectangles1256 / 1400
- Robot Path337 / 623
Advanced Techniques
- Meet in the Middle7313 / 10031
- Hamming Distance3451 / 3773
- Corner Subgrid Check380 / 579
- Corner Subgrid Count2382 / 2682
- Reachable Nodes2462 / 2644
- Reachability Queries1650 / 1936
- Cut and Paste1686 / 1862
- Substring Reversals1483 / 1605
- Reversals and Sums1508 / 1614
- Necessary Roads2156 / 2212
- Necessary Cities2007 / 2098
- Eulerian Subgraphs868 / 912
- Monster Game I1276 / 1415
- Monster Game II1130 / 1206
- Subarray Squares1592 / 1855
- Houses and Schools866 / 1032
- Knuth Division1041 / 1169
- Apples and Bananas1194 / 1295
- One Bit Positions925 / 1006
- Signal Processing896 / 957
- New Roads Queries2432 / 2936
- Dynamic Connectivity1117 / 1255
- Parcel Delivery857 / 943
- Task Assignment995 / 1069
- Distinct Routes II652 / 739
Sliding Window Problems
- Sliding Window Sum6320 / 6548
- Sliding Window Minimum4708 / 5383
- Sliding Window Xor4638 / 4703
- Sliding Window Or2062 / 3501
- Sliding Window Distinct Values3187 / 3856
- Sliding Window Mode2552 / 2716
- Sliding Window Mex2389 / 2519
- Sliding Window Median14456 / 16481
- Sliding Window Cost9456 / 10898
- Sliding Window Inversions1322 / 1401
- Sliding Window Advertisement251 / 403
Interactive Problems
- Hidden Integer2477 / 2578
- Hidden Permutation1074 / 1253
- K-th Highest Score469 / 569
- Permuted Binary Strings576 / 590
- Colored Chairs529 / 557
- Inversion Sorting297 / 333
Bitwise Operations
- Counting Bits5478 / 7088
- Maximum Xor Subarray3262 / 3724
- Maximum Xor Subset1103 / 1205
- Number of Subset Xors968 / 988
- K Subset Xors495 / 587
- All Subarray Xors303 / 490
- Xor Pyramid Peak2194 / 2653
- Xor Pyramid Diagonal347 / 388
- Xor Pyramid Row302 / 355
- SOS Bit Problem2319 / 2462
- And Subset Count480 / 500
Construction Problems
- Inverse Inversions1805 / 1924
- Monotone Subsequences1090 / 1288
- Third Permutation443 / 536
- Permutation Prime Sums444 / 479
- Chess Tournament1274 / 1474
- Distinct Sums Grid142 / 219
- Filling Trominos249 / 452
- Grid Path Construction125 / 445
Advanced Graph Problems
- Nearest Shops778 / 1001
- Prüfer Code1620 / 1739
- Tree Traversals1318 / 1448
- Course Schedule II2075 / 2951
- Acyclic Graph Edges2330 / 2466
- Strongly Connected Edges1616 / 1897
- Even Outdegree Edges1453 / 1691
- Graph Girth3644 / 4129
- Fixed Length Walk Queries386 / 429
- Transfer Speeds Sum452 / 466
- MST Edge Check703 / 764
- MST Edge Set Check265 / 299
- MST Edge Cost426 / 445
- Network Breakdown1241 / 1349
- Tree Coin Collecting I376 / 408
- Tree Coin Collecting II209 / 242
- Tree Isomorphism I1149 / 1363
- Tree Isomorphism II944 / 1087
- Flight Route Requests528 / 651
- Critical Cities456 / 695
- Visiting Cities719 / 945
- Graph Coloring246 / 289
- Bus Companies293 / 300
- Split into Two Paths108 / 193
- Network Renovation983 / 1300
- Forbidden Cities893 / 1164
- Creating Offices441 / 576
- New Flight Routes350 / 936
Counting Problems
- Filled Subgrid Count I630 / 707
- Filled Subgrid Count II343 / 422
- All Letter Subgrid Count I192 / 284
- All Letter Subgrid Count II149 / 190
- Border Subgrid Count I105 / 182
- Border Subgrid Count II114 / 132
- Raab Game II115 / 131
- Empty String1782 / 2161
- Permutation Inversions1075 / 1185
- Counting Bishops418 / 464
- Counting Sequences711 / 765
- Grid Paths II809 / 1010
- Counting Permutations939 / 1058
- Grid Completion237 / 300
- Counting Reorders263 / 372
- Tournament Graph Distribution116 / 123
- Collecting Numbers Distribution123 / 131
- Functional Graph Distribution256 / 315
Additional Problems I
- Shortest Subsequence3116 / 4097
- Distinct Values Sum717 / 741
- Distinct Values Splits516 / 547
- Swap Game2123 / 2726
- Beautiful Permutation II597 / 904
- Multiplication Table7217 / 8035
- Bubble Sort Rounds I446 / 507
- Bubble Sort Rounds II297 / 332
- Nearest Campsites I197 / 229
- Nearest Campsites II192 / 205
- Advertisement4600 / 4872
- Special Substrings1024 / 1122
- Counting LCM Arrays295 / 322
- Square Subsets239 / 263
- Subarray Sum Constraints443 / 473
- Water Containers Moves191 / 201
- Water Containers Queries227 / 238
- Stack Weights617 / 737
- Maximum Average Subarrays184 / 202
- Subsets with Fixed Average226 / 245
- Two Array Average229 / 256
- Pyramid Array798 / 964
- Permutation Subsequence275 / 283
- Bit Inversions2426 / 2740
- Writing Numbers770 / 831
- Letter Pair Move Game213 / 293
- Maximum Building I2166 / 2258
- Sorting Methods803 / 857
- Cyclic Array1267 / 1438
- List of Sums511 / 663
Additional Problems II
- Bouncing Ball Steps252 / 278
- Bouncing Ball Cycle98 / 138
- Knight Moves Queries128 / 152
- K Subset Sums I205 / 264
- K Subset Sums II119 / 152
- Increasing Array II849 / 966
- Food Division544 / 651
- Swap Round Sorting429 / 531
- Binary Subsequences301 / 437
- School Excursion1453 / 1536
- Coin Grid938 / 1095
- Grid Coloring II146 / 189
- Programmers and Artists528 / 737
- Removing Digits II223 / 483
- Coin Arrangement348 / 465
- Replace with Difference137 / 163
- Grid Puzzle I567 / 620
- Grid Puzzle II549 / 601
- Bit Substrings412 / 499
- Reversal Sorting372 / 449
- Book Shop II1311 / 1490
- GCD Subsets439 / 451
- Minimum Cost Pairs151 / 195
- Same Sum Subsets123 / 242
- Mex Grid Queries883 / 1033
- Maximum Building II463 / 570
- Stick Divisions3948 / 4617
- Stick Difference70 / 272
- Coding Company1569 / 2051
- Two Stacks Sorting188 / 596