General
Introductory Problems
- Weird Algorithm174578 / 182394
- Missing Number150712 / 157556
- Repetitions131004 / 135950
- Increasing Array123453 / 127568
- Permutations108232 / 111358
- Number Spiral76852 / 83361
- Two Knights59281 / 61030
- Two Sets64424 / 68959
- Bit Strings73268 / 77134
- Trailing Zeros67904 / 72029
- Coin Piles60386 / 65709
- Palindrome Reorder56131 / 59066
- Gray Code38304 / 42711
- Tower of Hanoi35679 / 37039
- Creating Strings47346 / 48499
- Apple Division48018 / 53834
- Chessboard and Queens29233 / 29726
- Raab Game I7439 / 8355
- Mex Grid Construction7228 / 7577
- Knight Moves Grid7315 / 7477
- Grid Coloring I6139 / 6352
- Digit Queries20547 / 23568
- String Reorder5507 / 6291
- Grid Path Description11523 / 14770
Sorting and Searching
- Distinct Numbers86715 / 93330
- Apartments65197 / 71713
- Ferris Wheel62801 / 67272
- Concert Tickets50342 / 58078
- Restaurant Customers51251 / 55032
- Movie Festival49775 / 52485
- Sum of Two Values57630 / 64037
- Maximum Subarray Sum55024 / 57292
- Stick Lengths49327 / 51428
- Missing Coin Sum37697 / 38994
- Collecting Numbers38641 / 41153
- Collecting Numbers II16936 / 21117
- Playlist38564 / 43690
- Towers38574 / 41147
- Traffic Lights30010 / 33366
- Distinct Values Subarrays10071 / 11298
- Distinct Values Subsequences7762 / 8457
- Josephus Problem I23340 / 25509
- Josephus Problem II12733 / 17426
- Nested Ranges Check13905 / 15730
- Nested Ranges Count9321 / 10896
- Room Allocation22716 / 25861
- Factory Machines32902 / 35546
- Tasks and Deadlines26284 / 26799
- Reading Books21309 / 22735
- Sum of Three Values30743 / 33791
- Sum of Four Values19198 / 21187
- Nearest Smaller Values25724 / 26557
- Subarray Sums I34147 / 36222
- Subarray Sums II31129 / 36494
- Subarray Divisibility28222 / 30541
- Distinct Values Subarrays II17247 / 18755
- Array Division26718 / 28008
- Movie Festival II14485 / 17264
- Maximum Subarray Sum II13515 / 15934
Dynamic Programming
- Dice Combinations91000 / 96006
- Minimizing Coins78786 / 84306
- Coin Combinations I72047 / 77633
- Coin Combinations II61086 / 68617
- Removing Digits67789 / 69099
- Grid Paths I63754 / 65442
- Book Shop57487 / 62830
- Array Description42585 / 46947
- Counting Towers26460 / 27949
- Edit Distance42414 / 44616
- Longest Common Subsequence14462 / 14953
- Rectangle Cutting35014 / 38038
- Minimal Grid Path6698 / 11155
- Money Sums41321 / 42786
- Removal Game25520 / 33027
- Two Sets II32575 / 34857
- Mountain Range4606 / 7915
- Increasing Subsequence33130 / 37008
- Projects23254 / 25799
- Elevator Rides15191 / 18821
- Counting Tilings8916 / 9639
- Counting Numbers13297 / 14722
- Increasing Subsequence II5920 / 6930
Graph Algorithms
- Counting Rooms63310 / 66273
- Labyrinth44919 / 52856
- Building Roads55395 / 57256
- Message Route47995 / 49747
- Building Teams45333 / 47547
- Round Trip35932 / 38882
- Monsters25428 / 29413
- Shortest Routes I39623 / 43248
- Shortest Routes II32057 / 35625
- High Score20495 / 27735
- Flight Discount26232 / 30176
- Cycle Finding18536 / 22192
- Flight Routes18062 / 19955
- Round Trip II20092 / 22314
- Course Schedule26550 / 27859
- Longest Flight Route19428 / 23427
- Game Routes21200 / 22512
- Investigation16006 / 17085
- Planets Queries I13877 / 16037
- Planets Queries II5035 / 6261
- Planets Cycles8392 / 9284
- Road Reparation20643 / 21453
- Road Construction22515 / 23198
- Flight Routes Check17886 / 19244
- Planets and Kingdoms14559 / 15168
- Giant Pizza6129 / 6693
- Coin Collector9643 / 10556
- Mail Delivery7706 / 8375
- De Bruijn Sequence4070 / 4253
- Teleporters Path5967 / 6721
- Hamiltonian Flights9095 / 10288
- Knight's Tour3415 / 4091
- Download Speed5967 / 7778
- Police Chase4765 / 5292
- School Dance5220 / 5502
- Distinct Routes3694 / 4739
Range Queries
- Static Range Sum Queries44197 / 46123
- Static Range Minimum Queries30334 / 32466
- Dynamic Range Sum Queries31557 / 32901
- Dynamic Range Minimum Queries28507 / 29168
- Range Xor Queries29226 / 29612
- Range Update Queries23512 / 25112
- Forest Queries24247 / 25077
- Hotel Queries17155 / 18110
- List Removals14230 / 14913
- Salary Queries10959 / 13578
- Prefix Sum Queries9197 / 9889
- Pizzeria Queries7374 / 7627
- Visible Buildings Queries2208 / 2395
- Range Interval Queries1683 / 2241
- Subarray Sum Queries8523 / 9197
- Subarray Sum Queries II2482 / 2557
- Distinct Values Queries8073 / 9787
- Distinct Values Queries II1398 / 1582
- Increasing Array Queries3086 / 3511
- Movie Festival Queries1714 / 1885
- Forest Queries II5049 / 5401
- Range Updates and Sums7064 / 8267
- Polynomial Queries5189 / 6057
- Range Queries and Copies3678 / 3917
- Missing Coin Sum Queries856 / 1173
Tree Algorithms
- Subordinates36359 / 38802
- Tree Matching21009 / 24197
- Tree Diameter29734 / 31394
- Tree Distances I23052 / 24652
- Tree Distances II18780 / 19615
- Company Queries I21113 / 22148
- Company Queries II19730 / 20716
- Distance Queries17790 / 19003
- Counting Paths11230 / 11850
- Subtree Queries13208 / 14032
- Path Queries10648 / 11223
- Path Queries II4478 / 6569
- Distinct Colors10230 / 11184
- Finding a Centroid8326 / 8653
- Fixed-Length Paths I4167 / 5240
- Fixed-Length Paths II2033 / 3533
Mathematics
- Josephus Queries5777 / 7209
- Exponentiation28196 / 29997
- Exponentiation II19719 / 23392
- Counting Divisors25940 / 29197
- Common Divisors16655 / 19212
- Sum of Divisors9484 / 13885
- Divisor Analysis6511 / 8609
- Prime Multiples7567 / 8742
- Counting Coprime Pairs5015 / 5779
- Next Prime2627 / 2989
- Binomial Coefficients12088 / 13332
- Creating Strings II10028 / 10555
- Distributing Apples9574 / 10272
- Christmas Party7948 / 8472
- Permutation Order1255 / 1290
- Permutation Rounds1804 / 1992
- Bracket Sequences I5319 / 5770
- Bracket Sequences II2814 / 3202
- Counting Necklaces2575 / 2783
- Counting Grids2167 / 2299
- Fibonacci Numbers7957 / 9892
- Throwing Dice4200 / 4545
- Graph Paths I4074 / 4339
- Graph Paths II3411 / 3571
- System of Linear Equations638 / 692
- Sum of Four Squares907 / 1090
- Triangle Number Sums792 / 949
- Dice Probability3566 / 3830
- Moving Robots1854 / 1953
- Candy Lottery1904 / 3550
- Inversion Probability571 / 2630
- Stick Game4090 / 4187
- Nim Game I5446 / 5642
- Nim Game II4317 / 4481
- Stair Game2917 / 3161
- Grundy's Game2044 / 2675
- Another Game2309 / 2483
String Algorithms
- Word Combinations7052 / 9985
- String Matching13439 / 17733
- Finding Borders9890 / 10760
- Finding Periods7076 / 7963
- Minimal Rotation3515 / 5146
- Longest Palindrome5195 / 6738
- All Palindromes923 / 1034
- Required Substring1989 / 2949
- Palindrome Queries2429 / 2804
- Finding Patterns2293 / 3174
- Counting Patterns2176 / 2657
- Pattern Positions1832 / 2202
- Distinct Substrings2053 / 2431
- Distinct Subsequences1320 / 1397
- Repeating Substring2230 / 2557
- String Functions1962 / 2055
- Inverse Suffix Array362 / 414
- String Transform671 / 796
- Substring Order I1408 / 1556
- Substring Order II952 / 1220
- Substring Distribution1312 / 1418
Geometry
- Point Location Test8466 / 9390
- Line Segment Intersection5025 / 6249
- Polygon Area5771 / 6088
- Point in Polygon3226 / 4053
- Polygon Lattice Points2620 / 2803
- Minimum Euclidean Distance2318 / 3240
- Convex Hull3859 / 4574
- Maximum Manhattan Distances811 / 843
- All Manhattan Distances842 / 926
- Intersection Points2284 / 2458
- Line Segments Trace I447 / 463
- Line Segments Trace II372 / 391
- Lines and Queries I493 / 517
- Lines and Queries II439 / 459
- Area of Rectangles1336 / 1487
- Robot Path363 / 668
Advanced Techniques
- Meet in the Middle8071 / 10873
- Hamming Distance3602 / 3936
- Corner Subgrid Check295 / 671
- Corner Subgrid Count2472 / 2810
- Reachable Nodes2574 / 2758
- Reachability Queries1727 / 2021
- Cut and Paste1768 / 1953
- Substring Reversals1561 / 1686
- Reversals and Sums1583 / 1691
- Necessary Roads2289 / 2346
- Necessary Cities2127 / 2220
- Eulerian Subgraphs905 / 954
- Monster Game I1361 / 1508
- Monster Game II1201 / 1282
- Subarray Squares1701 / 1974
- Houses and Schools922 / 1091
- Knuth Division1106 / 1239
- Apples and Bananas1282 / 1386
- One Bit Positions976 / 1061
- Signal Processing953 / 1017
- New Roads Queries2586 / 3105
- Dynamic Connectivity1175 / 1316
- Parcel Delivery928 / 1015
- Task Assignment1071 / 1158
- Distinct Routes II707 / 798
Sliding Window Problems
- Sliding Window Sum7700 / 7955
- Sliding Window Minimum5770 / 6568
- Sliding Window Xor5671 / 5746
- Sliding Window Or2550 / 4234
- Sliding Window Distinct Values4011 / 4700
- Sliding Window Mode3134 / 3320
- Sliding Window Mex2962 / 3117
- Sliding Window Median15128 / 17195
- Sliding Window Cost9881 / 11353
- Sliding Window Inversions1599 / 1695
- Sliding Window Advertisement309 / 489
Interactive Problems
- Hidden Integer2805 / 2924
- Hidden Permutation1259 / 1458
- K-th Highest Score577 / 692
- Permuted Binary Strings677 / 696
- Colored Chairs633 / 671
- Inversion Sorting370 / 417
Bitwise Operations
- Counting Bits6077 / 7805
- Maximum Xor Subarray3602 / 4111
- Maximum Xor Subset1327 / 1451
- Number of Subset Xors1156 / 1180
- K Subset Xors598 / 700
- All Subarray Xors360 / 562
- Xor Pyramid Peak2387 / 2861
- Xor Pyramid Diagonal409 / 459
- Xor Pyramid Row354 / 413
- SOS Bit Problem2521 / 2671
- And Subset Count580 / 604
Construction Problems
- Inverse Inversions2013 / 2148
- Monotone Subsequences1219 / 1439
- Third Permutation530 / 655
- Permutation Prime Sums533 / 573
- Chess Tournament1362 / 1571
- Distinct Sums Grid186 / 276
- Filling Trominos299 / 517
- Grid Path Construction164 / 486
Advanced Graph Problems
- Nearest Shops912 / 1174
- Prüfer Code1696 / 1819
- Tree Traversals1394 / 1526
- Course Schedule II2301 / 3228
- Acyclic Graph Edges2427 / 2570
- Strongly Connected Edges1753 / 2040
- Even Outdegree Edges1550 / 1801
- Graph Girth3899 / 4399
- Fixed Length Walk Queries450 / 500
- Transfer Speeds Sum519 / 535
- MST Edge Check839 / 910
- MST Edge Set Check308 / 349
- MST Edge Cost503 / 524
- Network Breakdown1322 / 1436
- Tree Coin Collecting I440 / 477
- Tree Coin Collecting II249 / 285
- Tree Isomorphism I1216 / 1435
- Tree Isomorphism II1006 / 1152
- Flight Route Requests570 / 705
- Critical Cities490 / 737
- Visiting Cities752 / 988
- Graph Coloring283 / 329
- Bus Companies329 / 339
- Split into Two Paths130 / 225
- Network Renovation1024 / 1349
- Forbidden Cities956 / 1238
- Creating Offices467 / 607
- New Flight Routes396 / 1018
Counting Problems
- Filled Subgrid Count I748 / 835
- Filled Subgrid Count II405 / 501
- All Letter Subgrid Count I230 / 333
- All Letter Subgrid Count II168 / 220
- Border Subgrid Count I121 / 209
- Border Subgrid Count II133 / 155
- Raab Game II138 / 158
- Empty String1887 / 2288
- Permutation Inversions1118 / 1233
- Counting Bishops436 / 486
- Counting Sequences754 / 809
- Grid Paths II836 / 1053
- Counting Permutations972 / 1097
- Grid Completion251 / 318
- Counting Reorders290 / 404
- Tournament Graph Distribution137 / 147
- Collecting Numbers Distribution144 / 151
- Functional Graph Distribution270 / 332
Additional Problems I
- Shortest Subsequence3229 / 4226
- Distinct Values Sum829 / 853
- Distinct Values Splits585 / 627
- Swap Game2234 / 2855
- Beautiful Permutation II722 / 1119
- Multiplication Table7679 / 8527
- Bubble Sort Rounds I526 / 598
- Bubble Sort Rounds II360 / 401
- Nearest Campsites I228 / 266
- Nearest Campsites II221 / 238
- Advertisement4855 / 5135
- Special Substrings1073 / 1175
- Counting LCM Arrays352 / 384
- Square Subsets270 / 297
- Subarray Sum Constraints544 / 579
- Water Containers Moves218 / 232
- Water Containers Queries253 / 267
- Stack Weights642 / 768
- Maximum Average Subarrays214 / 234
- Subsets with Fixed Average254 / 277
- Two Array Average259 / 289
- Pyramid Array847 / 1019
- Permutation Subsequence302 / 313
- Bit Inversions2534 / 2852
- Writing Numbers800 / 866
- Letter Pair Move Game228 / 317
- Maximum Building I2253 / 2352
- Sorting Methods831 / 888
- Cyclic Array1351 / 1525
- List of Sums534 / 692
Additional Problems II
- Bouncing Ball Steps299 / 332
- Bouncing Ball Cycle123 / 171
- Knight Moves Queries152 / 183
- K Subset Sums I238 / 303
- K Subset Sums II146 / 183
- Increasing Array II892 / 1017
- Food Division568 / 678
- Swap Round Sorting443 / 549
- Binary Subsequences313 / 453
- School Excursion1517 / 1603
- Coin Grid996 / 1159
- Grid Coloring II165 / 214
- Programmers and Artists553 / 771
- Removing Digits II239 / 511
- Coin Arrangement367 / 486
- Replace with Difference161 / 194
- Grid Puzzle I593 / 651
- Grid Puzzle II576 / 630
- Bit Substrings438 / 530
- Reversal Sorting388 / 467
- Book Shop II1403 / 1600
- GCD Subsets498 / 514
- Minimum Cost Pairs170 / 216
- Same Sum Subsets150 / 288
- Mex Grid Queries912 / 1067
- Maximum Building II482 / 593
- Stick Divisions4110 / 4795
- Stick Difference96 / 318
- Coding Company1638 / 2138
- Two Stacks Sorting203 / 634