General
Introductory Problems
- Weird Algorithm158868 / 166220
- Missing Number137064 / 143573
- Repetitions119232 / 123949
- Increasing Array112188 / 116127
- Permutations98618 / 101571
- Number Spiral69705 / 75888
- Two Knights53347 / 55008
- Two Sets58044 / 62395
- Bit Strings66380 / 70038
- Trailing Zeros61735 / 65602
- Coin Piles54705 / 59788
- Palindrome Reorder50902 / 53699
- Gray Code34140 / 38295
- Tower of Hanoi31754 / 33027
- Creating Strings42910 / 44007
- Apple Division43117 / 48672
- Chessboard and Queens26006 / 26472
- Raab Game I5066 / 5761
- Mex Grid Construction4925 / 5213
- Knight Moves Grid4903 / 5013
- Grid Coloring I4110 / 4250
- Digit Queries18327 / 21252
- String Reorder3775 / 4375
- Grid Path Description10168 / 13189
Sorting and Searching
- Distinct Numbers78349 / 84637
- Apartments58400 / 64702
- Ferris Wheel56036 / 60364
- Concert Tickets44880 / 52157
- Restaurant Customers45731 / 49302
- Movie Festival44133 / 46710
- Sum of Two Values51365 / 57409
- Maximum Subarray Sum49496 / 51655
- Stick Lengths44201 / 46204
- Missing Coin Sum33382 / 34583
- Collecting Numbers34291 / 36662
- Collecting Numbers II14407 / 18352
- Playlist34206 / 38981
- Towers34335 / 36775
- Traffic Lights26645 / 29772
- Distinct Values Subarrays6770 / 7931
- Distinct Values Subsequences5211 / 5767
- Josephus Problem I20441 / 22505
- Josephus Problem II11063 / 15259
- Nested Ranges Check11869 / 13618
- Nested Ranges Count7989 / 9423
- Room Allocation20046 / 22971
- Factory Machines28801 / 31316
- Tasks and Deadlines23042 / 23532
- Reading Books18683 / 20008
- Sum of Three Values27325 / 30222
- Sum of Four Values16971 / 18871
- Nearest Smaller Values22789 / 23572
- Subarray Sums I30230 / 32201
- Subarray Sums II27470 / 32549
- Subarray Divisibility24926 / 27126
- Distinct Values Subarrays II15027 / 16496
- Array Division23647 / 24872
- Movie Festival II12635 / 15216
- Maximum Subarray Sum II11755 / 14004
Dynamic Programming
- Dice Combinations81402 / 86078
- Minimizing Coins70359 / 75530
- Coin Combinations I64261 / 69499
- Coin Combinations II54318 / 61387
- Removing Digits60474 / 61696
- Grid Paths I56844 / 58446
- Book Shop50885 / 55883
- Array Description37351 / 41452
- Counting Towers22826 / 24194
- Edit Distance37501 / 39571
- Longest Common Subsequence9845 / 10210
- Rectangle Cutting30940 / 33762
- Minimal Grid Path4261 / 7684
- Money Sums36752 / 38132
- Removal Game21934 / 29279
- Two Sets II28872 / 31055
- Mountain Range2962 / 5434
- Increasing Subsequence29557 / 33164
- Projects20356 / 22728
- Elevator Rides13078 / 16421
- Counting Tilings7648 / 8331
- Counting Numbers10727 / 12081
- Increasing Subsequence II4519 / 5254
Graph Algorithms
- Counting Rooms56104 / 58906
- Labyrinth38924 / 46502
- Building Roads48794 / 50562
- Message Route42081 / 43754
- Building Teams39740 / 41878
- Round Trip31486 / 34259
- Monsters21708 / 25523
- Shortest Routes I34581 / 38103
- Shortest Routes II27983 / 31324
- High Score17128 / 24039
- Flight Discount22220 / 25945
- Cycle Finding15728 / 19232
- Flight Routes15284 / 17052
- Round Trip II17333 / 19439
- Course Schedule22900 / 24169
- Longest Flight Route16288 / 20102
- Game Routes18154 / 19408
- Investigation13471 / 14470
- Planets Queries I11673 / 13624
- Planets Queries II4239 / 5357
- Planets Cycles7153 / 7975
- Road Reparation17748 / 18500
- Road Construction19372 / 19983
- Flight Routes Check15529 / 16819
- Planets and Kingdoms12409 / 12911
- Giant Pizza5209 / 5720
- Coin Collector8133 / 8997
- Mail Delivery6761 / 7391
- De Bruijn Sequence3559 / 3722
- Teleporters Path5159 / 5886
- Hamiltonian Flights7760 / 8853
- Knight's Tour2916 / 3518
- Download Speed5167 / 6886
- Police Chase4131 / 4630
- School Dance4506 / 4757
- Distinct Routes3197 / 4172
Range Queries
- Static Range Sum Queries39059 / 40783
- Static Range Minimum Queries27122 / 29034
- Dynamic Range Sum Queries28144 / 29364
- Dynamic Range Minimum Queries25476 / 26066
- Range Xor Queries26325 / 26667
- Range Update Queries20918 / 22393
- Forest Queries21564 / 22350
- Hotel Queries15181 / 16094
- List Removals12588 / 13230
- Salary Queries9511 / 11961
- Prefix Sum Queries8107 / 8767
- Pizzeria Queries6518 / 6754
- Visible Buildings Queries1594 / 1739
- Range Interval Queries1243 / 1671
- Subarray Sum Queries7691 / 8329
- Subarray Sum Queries II1758 / 1821
- Distinct Values Queries7181 / 8829
- Distinct Values Queries II1030 / 1182
- Increasing Array Queries2762 / 3157
- Movie Festival Queries1428 / 1588
- Forest Queries II4577 / 4922
- Range Updates and Sums6216 / 7361
- Polynomial Queries4520 / 5289
- Range Queries and Copies3275 / 3499
- Missing Coin Sum Queries737 / 964
Tree Algorithms
- Subordinates32118 / 34339
- Tree Matching18258 / 21205
- Tree Diameter26173 / 27731
- Tree Distances I20028 / 21505
- Tree Distances II16393 / 17084
- Company Queries I18213 / 19146
- Company Queries II17110 / 17939
- Distance Queries15510 / 16610
- Counting Paths9756 / 10329
- Subtree Queries11706 / 12476
- Path Queries9381 / 9937
- Path Queries II3856 / 5781
- Distinct Colors9041 / 9955
- Finding a Centroid7310 / 7602
- Fixed-Length Paths I3550 / 4557
- Fixed-Length Paths II1675 / 3031
Mathematics
- Josephus Queries5028 / 6336
- Exponentiation25493 / 27216
- Exponentiation II17877 / 21376
- Counting Divisors23278 / 26274
- Common Divisors15065 / 17459
- Sum of Divisors8402 / 12563
- Divisor Analysis5777 / 7737
- Prime Multiples6694 / 7808
- Counting Coprime Pairs4398 / 5106
- Next Prime1914 / 2201
- Binomial Coefficients10778 / 11951
- Creating Strings II9039 / 9541
- Distributing Apples8636 / 9287
- Christmas Party7030 / 7532
- Permutation Order925 / 944
- Permutation Rounds1209 / 1344
- Bracket Sequences I4796 / 5220
- Bracket Sequences II2534 / 2894
- Counting Necklaces2308 / 2496
- Counting Grids1915 / 2038
- Fibonacci Numbers7263 / 9098
- Throwing Dice3776 / 4104
- Graph Paths I3629 / 3887
- Graph Paths II3030 / 3174
- System of Linear Equations443 / 487
- Sum of Four Squares656 / 780
- Triangle Number Sums570 / 696
- Dice Probability3254 / 3509
- Moving Robots1669 / 1765
- Candy Lottery1564 / 3166
- Inversion Probability419 / 2364
- Stick Game3692 / 3783
- Nim Game I4897 / 5077
- Nim Game II3873 / 4025
- Stair Game2633 / 2861
- Grundy's Game1831 / 2397
- Another Game2062 / 2224
String Algorithms
- Word Combinations6206 / 8958
- String Matching12034 / 16054
- Finding Borders8785 / 9602
- Finding Periods6246 / 7083
- Minimal Rotation3035 / 4593
- Longest Palindrome4587 / 6062
- All Palindromes629 / 714
- Required Substring1749 / 2652
- Palindrome Queries2142 / 2484
- Finding Patterns2016 / 2847
- Counting Patterns1905 / 2360
- Pattern Positions1602 / 1953
- Distinct Substrings1815 / 2164
- Distinct Subsequences1134 / 1207
- Repeating Substring1950 / 2265
- String Functions1706 / 1787
- Inverse Suffix Array238 / 281
- String Transform554 / 671
- Substring Order I1231 / 1374
- Substring Order II814 / 1058
- Substring Distribution1145 / 1243
Geometry
- Point Location Test7736 / 8616
- Line Segment Intersection4593 / 5749
- Polygon Area5300 / 5604
- Point in Polygon2916 / 3718
- Polygon Lattice Points2463 / 2545
- Minimum Euclidean Distance2108 / 3003
- Convex Hull3535 / 4222
- Maximum Manhattan Distances599 / 620
- All Manhattan Distances592 / 646
- Intersection Points2072 / 2234
- Line Segments Trace I322 / 333
- Line Segments Trace II265 / 279
- Lines and Queries I370 / 385
- Lines and Queries II319 / 330
- Area of Rectangles1194 / 1336
- Robot Path318 / 590
Advanced Techniques
- Meet in the Middle7004 / 9668
- Hamming Distance3365 / 3663
- Corner Subgrid Check329 / 509
- Corner Subgrid Count2316 / 2597
- Reachable Nodes2369 / 2545
- Reachability Queries1578 / 1858
- Cut and Paste1593 / 1769
- Substring Reversals1394 / 1513
- Reversals and Sums1405 / 1509
- Necessary Roads2033 / 2088
- Necessary Cities1887 / 1974
- Eulerian Subgraphs834 / 877
- Monster Game I1209 / 1341
- Monster Game II1072 / 1147
- Subarray Squares1484 / 1747
- Houses and Schools808 / 964
- Knuth Division986 / 1111
- Apples and Bananas1123 / 1218
- One Bit Positions884 / 964
- Signal Processing843 / 902
- New Roads Queries2285 / 2768
- Dynamic Connectivity1046 / 1178
- Parcel Delivery809 / 894
- Task Assignment950 / 1012
- Distinct Routes II610 / 695
Sliding Window Problems
- Sliding Window Sum5326 / 5527
- Sliding Window Minimum3972 / 4547
- Sliding Window Xor3897 / 3946
- Sliding Window Or1701 / 2958
- Sliding Window Distinct Values2611 / 3258
- Sliding Window Mode2181 / 2301
- Sliding Window Mex2000 / 2109
- Sliding Window Median14029 / 16020
- Sliding Window Cost9196 / 10615
- Sliding Window Inversions1118 / 1191
- Sliding Window Advertisement212 / 338
Interactive Problems
- Hidden Integer2130 / 2210
- Hidden Permutation901 / 1055
- K-th Highest Score392 / 481
- Permuted Binary Strings486 / 498
- Colored Chairs441 / 464
- Inversion Sorting251 / 280
Bitwise Operations
- Counting Bits5107 / 6601
- Maximum Xor Subarray3055 / 3467
- Maximum Xor Subset959 / 1047
- Number of Subset Xors852 / 870
- K Subset Xors430 / 515
- All Subarray Xors262 / 433
- Xor Pyramid Peak2074 / 2518
- Xor Pyramid Diagonal306 / 342
- Xor Pyramid Row255 / 302
- SOS Bit Problem2181 / 2318
- And Subset Count403 / 416
Construction Problems
- Inverse Inversions1642 / 1750
- Monotone Subsequences999 / 1179
- Third Permutation388 / 470
- Permutation Prime Sums386 / 416
- Chess Tournament1223 / 1412
- Distinct Sums Grid116 / 182
- Filling Trominos239 / 428
- Grid Path Construction120 / 431
Advanced Graph Problems
- Nearest Shops664 / 862
- Prüfer Code1553 / 1670
- Tree Traversals1263 / 1390
- Course Schedule II1956 / 2795
- Acyclic Graph Edges2251 / 2386
- Strongly Connected Edges1617 / 1789
- Even Outdegree Edges1372 / 1601
- Graph Girth3464 / 3939
- Fixed Length Walk Queries341 / 373
- Transfer Speeds Sum391 / 403
- MST Edge Check593 / 644
- MST Edge Set Check226 / 256
- MST Edge Cost363 / 377
- Network Breakdown1160 / 1266
- Tree Coin Collecting I313 / 344
- Tree Coin Collecting II172 / 199
- Tree Isomorphism I1105 / 1319
- Tree Isomorphism II908 / 1049
- Flight Route Requests497 / 609
- Critical Cities425 / 656
- Visiting Cities684 / 906
- Graph Coloring216 / 253
- Bus Companies255 / 261
- Split into Two Paths89 / 160
- Network Renovation950 / 1261
- Forbidden Cities844 / 1102
- Creating Offices415 / 541
- New Flight Routes326 / 879
Counting Problems
- Filled Subgrid Count I542 / 607
- Filled Subgrid Count II288 / 356
- All Letter Subgrid Count I157 / 241
- All Letter Subgrid Count II119 / 153
- Border Subgrid Count I87 / 151
- Border Subgrid Count II90 / 107
- Raab Game II98 / 113
- Empty String1666 / 2032
- Permutation Inversions1037 / 1144
- Counting Bishops393 / 438
- Counting Sequences659 / 712
- Grid Paths II755 / 946
- Counting Permutations897 / 1014
- Grid Completion226 / 286
- Counting Reorders241 / 349
- Tournament Graph Distribution97 / 103
- Collecting Numbers Distribution108 / 115
- Functional Graph Distribution239 / 296
Additional Problems I
- Shortest Subsequence3016 / 3978
- Distinct Values Sum614 / 636
- Distinct Values Splits445 / 470
- Swap Game2092 / 2638
- Beautiful Permutation II481 / 733
- Multiplication Table6901 / 7682
- Bubble Sort Rounds I372 / 423
- Bubble Sort Rounds II243 / 276
- Nearest Campsites I166 / 192
- Nearest Campsites II163 / 174
- Advertisement4433 / 4696
- Special Substrings987 / 1081
- Counting LCM Arrays254 / 279
- Square Subsets206 / 229
- Subarray Sum Constraints347 / 371
- Water Containers Moves154 / 162
- Water Containers Queries187 / 196
- Stack Weights585 / 698
- Maximum Average Subarrays152 / 168
- Subsets with Fixed Average194 / 210
- Two Array Average184 / 206
- Pyramid Array748 / 910
- Permutation Subsequence230 / 236
- Bit Inversions2335 / 2646
- Writing Numbers738 / 798
- Letter Pair Move Game202 / 280
- Maximum Building I2091 / 2181
- Sorting Methods768 / 822
- Cyclic Array1200 / 1365
- List of Sums488 / 636
Additional Problems II
- Bouncing Ball Steps215 / 236
- Bouncing Ball Cycle87 / 124
- Knight Moves Queries108 / 130
- K Subset Sums I169 / 221
- K Subset Sums II93 / 121
- Increasing Array II798 / 915
- Food Division518 / 625
- Swap Round Sorting416 / 513
- Binary Subsequences292 / 427
- School Excursion1390 / 1473
- Coin Grid886 / 1034
- Grid Coloring II126 / 165
- Programmers and Artists496 / 693
- Removing Digits II214 / 470
- Coin Arrangement330 / 443
- Replace with Difference122 / 145
- Grid Puzzle I537 / 591
- Grid Puzzle II512 / 565
- Bit Substrings393 / 476
- Reversal Sorting354 / 429
- Book Shop II1236 / 1411
- GCD Subsets386 / 398
- Minimum Cost Pairs130 / 169
- Same Sum Subsets107 / 198
- Mex Grid Queries849 / 994
- Maximum Building II449 / 554
- Stick Divisions3833 / 4494
- Stick Difference57 / 232
- Coding Company1497 / 1965
- Two Stacks Sorting175 / 568