General
Introductory Problems
- Weird Algorithm167421 / 175022
- Missing Number144560 / 151245
- Repetitions125756 / 130595
- Increasing Array118401 / 122424
- Permutations103954 / 106997
- Number Spiral73628 / 79997
- Two Knights56680 / 58399
- Two Sets61623 / 66061
- Bit Strings70315 / 74097
- Trailing Zeros65235 / 69273
- Coin Piles57928 / 63143
- Palindrome Reorder53885 / 56764
- Gray Code36584 / 40894
- Tower of Hanoi34031 / 35351
- Creating Strings45428 / 46557
- Apple Division45937 / 51648
- Chessboard and Queens27897 / 28375
- Raab Game I6444 / 7278
- Mex Grid Construction6275 / 6594
- Knight Moves Grid6321 / 6458
- Grid Coloring I5301 / 5485
- Digit Queries19630 / 22617
- String Reorder4799 / 5513
- Grid Path Description10976 / 14123
Sorting and Searching
- Distinct Numbers82956 / 89416
- Apartments62104 / 68534
- Ferris Wheel59651 / 64032
- Concert Tickets47867 / 55402
- Restaurant Customers48704 / 52415
- Movie Festival47135 / 49797
- Sum of Two Values54742 / 61002
- Maximum Subarray Sum52494 / 54726
- Stick Lengths46928 / 48999
- Missing Coin Sum35717 / 36972
- Collecting Numbers36597 / 39045
- Collecting Numbers II15760 / 19845
- Playlist36550 / 41532
- Towers36616 / 39126
- Traffic Lights28445 / 31701
- Distinct Values Subarrays8577 / 9787
- Distinct Values Subsequences6572 / 7215
- Josephus Problem I21949 / 24067
- Josephus Problem II11981 / 16422
- Nested Ranges Check12950 / 14746
- Nested Ranges Count8726 / 10236
- Room Allocation21455 / 24503
- Factory Machines30996 / 33583
- Tasks and Deadlines24726 / 25226
- Reading Books20008 / 21385
- Sum of Three Values29174 / 32159
- Sum of Four Values18174 / 20111
- Nearest Smaller Values24357 / 25168
- Subarray Sums I32303 / 34341
- Subarray Sums II29447 / 34673
- Subarray Divisibility26640 / 28893
- Distinct Values Subarrays II16226 / 17712
- Array Division25261 / 26523
- Movie Festival II13613 / 16317
- Maximum Subarray Sum II12665 / 15005
Dynamic Programming
- Dice Combinations86488 / 91379
- Minimizing Coins74732 / 80100
- Coin Combinations I68365 / 73801
- Coin Combinations II57833 / 65163
- Removing Digits64313 / 65577
- Grid Paths I60481 / 62136
- Book Shop54267 / 59463
- Array Description40030 / 44298
- Counting Towers24586 / 26016
- Edit Distance40046 / 42193
- Longest Common Subsequence12191 / 12623
- Rectangle Cutting32979 / 35919
- Minimal Grid Path5454 / 9396
- Money Sums38998 / 40424
- Removal Game23713 / 31118
- Two Sets II30642 / 32879
- Mountain Range3819 / 6705
- Increasing Subsequence31295 / 35054
- Projects21804 / 24273
- Elevator Rides14059 / 17538
- Counting Tilings8291 / 8998
- Counting Numbers12032 / 13427
- Increasing Subsequence II5299 / 6156
Graph Algorithms
- Counting Rooms59706 / 62615
- Labyrinth41835 / 49607
- Building Roads52090 / 53917
- Message Route45003 / 46725
- Building Teams42506 / 44692
- Round Trip33563 / 36422
- Monsters23446 / 27335
- Shortest Routes I37105 / 40690
- Shortest Routes II29959 / 33440
- High Score18747 / 25822
- Flight Discount24087 / 27940
- Cycle Finding17023 / 20620
- Flight Routes16526 / 18368
- Round Trip II18556 / 20727
- Course Schedule24687 / 25989
- Longest Flight Route17751 / 21662
- Game Routes19533 / 20829
- Investigation14580 / 15616
- Planets Queries I12667 / 14743
- Planets Queries II4632 / 5804
- Planets Cycles7752 / 8622
- Road Reparation19102 / 19884
- Road Construction20986 / 21647
- Flight Routes Check16650 / 17980
- Planets and Kingdoms13533 / 14057
- Giant Pizza5718 / 6255
- Coin Collector8889 / 9784
- Mail Delivery7220 / 7875
- De Bruijn Sequence3833 / 4009
- Teleporters Path5559 / 6302
- Hamiltonian Flights8412 / 9542
- Knight's Tour3212 / 3863
- Download Speed5584 / 7362
- Police Chase4447 / 4961
- School Dance4877 / 5147
- Distinct Routes3450 / 4467
Range Queries
- Static Range Sum Queries41776 / 43632
- Static Range Minimum Queries28905 / 30936
- Dynamic Range Sum Queries29960 / 31257
- Dynamic Range Minimum Queries27117 / 27754
- Range Xor Queries27899 / 28276
- Range Update Queries22309 / 23874
- Forest Queries22910 / 23716
- Hotel Queries16217 / 17152
- List Removals13485 / 14143
- Salary Queries10281 / 12833
- Prefix Sum Queries8714 / 9387
- Pizzeria Queries6997 / 7247
- Visible Buildings Queries1926 / 2097
- Range Interval Queries1491 / 1997
- Subarray Sum Queries8117 / 8778
- Subarray Sum Queries II2149 / 2219
- Distinct Values Queries7681 / 9362
- Distinct Values Queries II1241 / 1408
- Increasing Array Queries2943 / 3357
- Movie Festival Queries1601 / 1766
- Forest Queries II4838 / 5186
- Range Updates and Sums6696 / 7875
- Polynomial Queries4944 / 5799
- Range Queries and Copies3513 / 3746
- Missing Coin Sum Queries842 / 1092
Tree Algorithms
- Subordinates34183 / 36548
- Tree Matching19510 / 22578
- Tree Diameter27874 / 29490
- Tree Distances I21437 / 22996
- Tree Distances II17482 / 18271
- Company Queries I19480 / 20490
- Company Queries II18207 / 19151
- Distance Queries16488 / 17666
- Counting Paths10379 / 10971
- Subtree Queries12410 / 13194
- Path Queries9994 / 10561
- Path Queries II4201 / 6208
- Distinct Colors9614 / 10552
- Finding a Centroid7794 / 8109
- Fixed-Length Paths I3863 / 4896
- Fixed-Length Paths II1850 / 3290
Mathematics
- Josephus Queries5420 / 6808
- Exponentiation26973 / 28735
- Exponentiation II18844 / 22443
- Counting Divisors24616 / 27715
- Common Divisors15887 / 18371
- Sum of Divisors8979 / 13266
- Divisor Analysis6175 / 8206
- Prime Multiples7157 / 8313
- Counting Coprime Pairs4739 / 5481
- Next Prime2309 / 2643
- Binomial Coefficients11481 / 12699
- Creating Strings II9566 / 10078
- Distributing Apples9110 / 9780
- Christmas Party7506 / 8024
- Permutation Order1102 / 1130
- Permutation Rounds1554 / 1725
- Bracket Sequences I5062 / 5498
- Bracket Sequences II2679 / 3059
- Counting Necklaces2461 / 2659
- Counting Grids2049 / 2175
- Fibonacci Numbers7625 / 9514
- Throwing Dice3995 / 4336
- Graph Paths I3862 / 4124
- Graph Paths II3224 / 3374
- System of Linear Equations555 / 601
- Sum of Four Squares816 / 954
- Triangle Number Sums692 / 834
- Dice Probability3416 / 3673
- Moving Robots1776 / 1874
- Candy Lottery1744 / 3371
- Inversion Probability505 / 2511
- Stick Game3900 / 3991
- Nim Game I5205 / 5395
- Nim Game II4114 / 4274
- Stair Game2797 / 3036
- Grundy's Game1946 / 2549
- Another Game2199 / 2366
String Algorithms
- Word Combinations6663 / 9516
- String Matching12786 / 16957
- Finding Borders9391 / 10241
- Finding Periods6666 / 7535
- Minimal Rotation3292 / 4893
- Longest Palindrome4907 / 6410
- All Palindromes782 / 881
- Required Substring1902 / 2835
- Palindrome Queries2315 / 2682
- Finding Patterns2190 / 3044
- Counting Patterns2080 / 2551
- Pattern Positions1747 / 2112
- Distinct Substrings1975 / 2342
- Distinct Subsequences1254 / 1330
- Repeating Substring2131 / 2452
- String Functions1868 / 1956
- Inverse Suffix Array321 / 371
- String Transform636 / 760
- Substring Order I1358 / 1504
- Substring Order II903 / 1169
- Substring Distribution1257 / 1360
Geometry
- Point Location Test8154 / 9063
- Line Segment Intersection4825 / 6024
- Polygon Area5565 / 5871
- Point in Polygon3083 / 3902
- Polygon Lattice Points2587 / 2673
- Minimum Euclidean Distance2225 / 3136
- Convex Hull3731 / 4439
- Maximum Manhattan Distances713 / 741
- All Manhattan Distances712 / 782
- Intersection Points2202 / 2374
- Line Segments Trace I396 / 409
- Line Segments Trace II328 / 345
- Lines and Queries I444 / 463
- Lines and Queries II393 / 407
- Area of Rectangles1272 / 1419
- Robot Path341 / 635
Advanced Techniques
- Meet in the Middle7393 / 10126
- Hamming Distance3485 / 3809
- Corner Subgrid Check386 / 590
- Corner Subgrid Count2393 / 2700
- Reachable Nodes2481 / 2666
- Reachability Queries1660 / 1947
- Cut and Paste1695 / 1873
- Substring Reversals1494 / 1617
- Reversals and Sums1518 / 1625
- Necessary Roads2176 / 2233
- Necessary Cities2028 / 2120
- Eulerian Subgraphs872 / 918
- Monster Game I1289 / 1430
- Monster Game II1137 / 1215
- Subarray Squares1612 / 1877
- Houses and Schools878 / 1045
- Knuth Division1058 / 1188
- Apples and Bananas1211 / 1313
- One Bit Positions933 / 1015
- Signal Processing905 / 967
- New Roads Queries2462 / 2971
- Dynamic Connectivity1125 / 1265
- Parcel Delivery870 / 956
- Task Assignment1006 / 1083
- Distinct Routes II663 / 752
Sliding Window Problems
- Sliding Window Sum6645 / 6877
- Sliding Window Minimum4955 / 5657
- Sliding Window Xor4903 / 4972
- Sliding Window Or2185 / 3678
- Sliding Window Distinct Values3396 / 4072
- Sliding Window Mode2716 / 2885
- Sliding Window Mex2531 / 2669
- Sliding Window Median14621 / 16654
- Sliding Window Cost9556 / 11006
- Sliding Window Inversions1385 / 1467
- Sliding Window Advertisement275 / 430
Interactive Problems
- Hidden Integer2569 / 2675
- Hidden Permutation1135 / 1319
- K-th Highest Score509 / 614
- Permuted Binary Strings614 / 629
- Colored Chairs573 / 605
- Inversion Sorting330 / 368
Bitwise Operations
- Counting Bits5611 / 7243
- Maximum Xor Subarray3328 / 3803
- Maximum Xor Subset1155 / 1262
- Number of Subset Xors1016 / 1038
- K Subset Xors525 / 619
- All Subarray Xors318 / 508
- Xor Pyramid Peak2239 / 2704
- Xor Pyramid Diagonal363 / 407
- Xor Pyramid Row314 / 369
- SOS Bit Problem2364 / 2510
- And Subset Count498 / 520
Construction Problems
- Inverse Inversions1870 / 1993
- Monotone Subsequences1136 / 1339
- Third Permutation475 / 570
- Permutation Prime Sums482 / 519
- Chess Tournament1309 / 1512
- Distinct Sums Grid170 / 250
- Filling Trominos277 / 481
- Grid Path Construction149 / 473
Advanced Graph Problems
- Nearest Shops800 / 1030
- Prüfer Code1628 / 1750
- Tree Traversals1331 / 1462
- Course Schedule II2118 / 3007
- Acyclic Graph Edges2345 / 2482
- Strongly Connected Edges1649 / 1930
- Even Outdegree Edges1468 / 1709
- Graph Girth3701 / 4189
- Fixed Length Walk Queries397 / 441
- Transfer Speeds Sum466 / 480
- MST Edge Check730 / 794
- MST Edge Set Check273 / 308
- MST Edge Cost439 / 459
- Network Breakdown1253 / 1363
- Tree Coin Collecting I397 / 430
- Tree Coin Collecting II220 / 254
- Tree Isomorphism I1158 / 1374
- Tree Isomorphism II953 / 1097
- Flight Route Requests533 / 660
- Critical Cities458 / 700
- Visiting Cities723 / 952
- Graph Coloring250 / 293
- Bus Companies296 / 304
- Split into Two Paths111 / 197
- Network Renovation989 / 1306
- Forbidden Cities902 / 1174
- Creating Offices446 / 584
- New Flight Routes357 / 948
Counting Problems
- Filled Subgrid Count I645 / 723
- Filled Subgrid Count II353 / 436
- All Letter Subgrid Count I199 / 294
- All Letter Subgrid Count II153 / 195
- Border Subgrid Count I107 / 187
- Border Subgrid Count II118 / 137
- Raab Game II120 / 138
- Empty String1804 / 2184
- Permutation Inversions1083 / 1195
- Counting Bishops421 / 468
- Counting Sequences722 / 777
- Grid Paths II817 / 1022
- Counting Permutations946 / 1066
- Grid Completion238 / 302
- Counting Reorders272 / 381
- Tournament Graph Distribution122 / 131
- Collecting Numbers Distribution129 / 136
- Functional Graph Distribution258 / 318
Additional Problems I
- Shortest Subsequence3144 / 4131
- Distinct Values Sum744 / 768
- Distinct Values Splits530 / 564
- Swap Game2151 / 2758
- Beautiful Permutation II629 / 952
- Multiplication Table7328 / 8156
- Bubble Sort Rounds I465 / 528
- Bubble Sort Rounds II312 / 349
- Nearest Campsites I203 / 237
- Nearest Campsites II198 / 212
- Advertisement4646 / 4920
- Special Substrings1033 / 1133
- Counting LCM Arrays304 / 332
- Square Subsets245 / 272
- Subarray Sum Constraints461 / 493
- Water Containers Moves197 / 208
- Water Containers Queries232 / 244
- Stack Weights623 / 745
- Maximum Average Subarrays189 / 209
- Subsets with Fixed Average231 / 253
- Two Array Average234 / 262
- Pyramid Array809 / 974
- Permutation Subsequence280 / 289
- Bit Inversions2457 / 2774
- Writing Numbers776 / 838
- Letter Pair Move Game215 / 297
- Maximum Building I2188 / 2281
- Sorting Methods810 / 865
- Cyclic Array1287 / 1459
- List of Sums516 / 670
Additional Problems II
- Bouncing Ball Steps268 / 295
- Bouncing Ball Cycle105 / 146
- Knight Moves Queries132 / 158
- K Subset Sums I213 / 273
- K Subset Sums II125 / 158
- Increasing Array II858 / 977
- Food Division548 / 657
- Swap Round Sorting431 / 534
- Binary Subsequences305 / 442
- School Excursion1465 / 1549
- Coin Grid943 / 1101
- Grid Coloring II149 / 194
- Programmers and Artists533 / 746
- Removing Digits II226 / 489
- Coin Arrangement354 / 471
- Replace with Difference145 / 172
- Grid Puzzle I572 / 627
- Grid Puzzle II556 / 609
- Bit Substrings419 / 508
- Reversal Sorting375 / 453
- Book Shop II1327 / 1509
- GCD Subsets447 / 460
- Minimum Cost Pairs154 / 199
- Same Sum Subsets130 / 255
- Mex Grid Queries890 / 1041
- Maximum Building II466 / 574
- Stick Divisions3981 / 4651
- Stick Difference71 / 278
- Coding Company1580 / 2065
- Two Stacks Sorting189 / 601