General
Introductory Problems
- Weird Algorithm180388 / 188375
- Missing Number155636 / 162621
- Repetitions135087 / 140135
- Increasing Array127390 / 131575
- Permutations111464 / 114668
- Number Spiral79263 / 85904
- Two Knights61224 / 63012
- Two Sets66529 / 71146
- Bit Strings75573 / 79516
- Trailing Zeros69979 / 74194
- Coin Piles62332 / 67752
- Palindrome Reorder57874 / 60859
- Gray Code39628 / 44155
- Tower of Hanoi36943 / 38344
- Creating Strings48754 / 49923
- Apple Division49573 / 55486
- Chessboard and Queens30201 / 30705
- Raab Game I8208 / 9162
- Mex Grid Construction7925 / 8308
- Knight Moves Grid8001 / 8181
- Grid Coloring I6742 / 6975
- Digit Queries21199 / 24242
- String Reorder5995 / 6833
- Grid Path Description11906 / 15201
Sorting and Searching
- Distinct Numbers89791 / 96565
- Apartments67445 / 74095
- Ferris Wheel65049 / 69629
- Concert Tickets52227 / 60118
- Restaurant Customers53018 / 56873
- Movie Festival51561 / 54320
- Sum of Two Values59670 / 66215
- Maximum Subarray Sum56767 / 59068
- Stick Lengths50829 / 52987
- Missing Coin Sum39040 / 40362
- Collecting Numbers39939 / 42495
- Collecting Numbers II17646 / 21894
- Playlist39867 / 45055
- Towers39786 / 42419
- Traffic Lights30986 / 34403
- Distinct Values Subarrays11098 / 12359
- Distinct Values Subsequences8560 / 9287
- Josephus Problem I24247 / 26454
- Josephus Problem II13170 / 18033
- Nested Ranges Check14487 / 16340
- Nested Ranges Count9694 / 11307
- Room Allocation23594 / 26788
- Factory Machines34240 / 36916
- Tasks and Deadlines27263 / 27782
- Reading Books22173 / 23623
- Sum of Three Values31844 / 34947
- Sum of Four Values19851 / 21877
- Nearest Smaller Values26697 / 27543
- Subarray Sums I35433 / 37529
- Subarray Sums II32341 / 37819
- Subarray Divisibility29182 / 31549
- Distinct Values Subarrays II17873 / 19399
- Array Division27651 / 28965
- Movie Festival II15094 / 17925
- Maximum Subarray Sum II14080 / 16550
Dynamic Programming
- Dice Combinations94193 / 99350
- Minimizing Coins81512 / 87187
- Coin Combinations I74481 / 80195
- Coin Combinations II63261 / 71003
- Removing Digits70242 / 71614
- Grid Paths I65993 / 67732
- Book Shop59589 / 65088
- Array Description44186 / 48625
- Counting Towers27656 / 29159
- Edit Distance43936 / 46205
- Longest Common Subsequence15916 / 16429
- Rectangle Cutting36211 / 39314
- Minimal Grid Path7517 / 12273
- Money Sums42749 / 44244
- Removal Game26706 / 34242
- Two Sets II33778 / 36073
- Mountain Range5227 / 8793
- Increasing Subsequence34269 / 38329
- Projects24229 / 26870
- Elevator Rides15958 / 19671
- Counting Tilings9355 / 10095
- Counting Numbers14007 / 15468
- Increasing Subsequence II6440 / 7542
Graph Algorithms
- Counting Rooms65663 / 68706
- Labyrinth46741 / 54758
- Building Roads57495 / 59399
- Message Route49880 / 51656
- Building Teams47076 / 49336
- Round Trip37372 / 40369
- Monsters26650 / 30690
- Shortest Routes I41356 / 45040
- Shortest Routes II33321 / 36955
- High Score21529 / 28852
- Flight Discount27519 / 31532
- Cycle Finding19467 / 23167
- Flight Routes18957 / 20873
- Round Trip II21032 / 23321
- Course Schedule27704 / 29055
- Longest Flight Route20359 / 24385
- Game Routes22156 / 23475
- Investigation16907 / 18008
- Planets Queries I14685 / 16879
- Planets Queries II5341 / 6616
- Planets Cycles8841 / 9748
- Road Reparation21667 / 22490
- Road Construction23601 / 24296
- Flight Routes Check18715 / 20091
- Planets and Kingdoms15315 / 15925
- Giant Pizza6454 / 7039
- Coin Collector10215 / 11148
- Mail Delivery8085 / 8764
- De Bruijn Sequence4264 / 4454
- Teleporters Path6261 / 7020
- Hamiltonian Flights9591 / 10822
- Knight's Tour3589 / 4280
- Download Speed6218 / 8056
- Police Chase4964 / 5497
- School Dance5463 / 5750
- Distinct Routes3854 / 4916
Range Queries
- Static Range Sum Queries46059 / 48069
- Static Range Minimum Queries31622 / 33824
- Dynamic Range Sum Queries32944 / 34329
- Dynamic Range Minimum Queries29737 / 30415
- Range Xor Queries30301 / 30695
- Range Update Queries24591 / 26225
- Forest Queries25197 / 26045
- Hotel Queries17963 / 18940
- List Removals14959 / 15654
- Salary Queries11618 / 14288
- Prefix Sum Queries9727 / 10432
- Pizzeria Queries7772 / 8030
- Visible Buildings Queries2462 / 2666
- Range Interval Queries1872 / 2483
- Subarray Sum Queries8938 / 9627
- Subarray Sum Queries II2829 / 2908
- Distinct Values Queries8449 / 10205
- Distinct Values Queries II1546 / 1743
- Increasing Array Queries3229 / 3660
- Movie Festival Queries1816 / 1989
- Forest Queries II5218 / 5581
- Range Updates and Sums7428 / 8657
- Polynomial Queries5436 / 6308
- Range Queries and Copies3827 / 4070
- Missing Coin Sum Queries928 / 1265
Tree Algorithms
- Subordinates37771 / 40270
- Tree Matching21992 / 25259
- Tree Diameter30977 / 32663
- Tree Distances I24116 / 25734
- Tree Distances II19686 / 20541
- Company Queries I22108 / 23174
- Company Queries II20681 / 21683
- Distance Queries18623 / 19871
- Counting Paths11842 / 12471
- Subtree Queries13829 / 14671
- Path Queries11180 / 11771
- Path Queries II4711 / 6842
- Distinct Colors10699 / 11688
- Finding a Centroid8686 / 9019
- Fixed-Length Paths I4373 / 5460
- Fixed-Length Paths II2163 / 3704
Mathematics
- Josephus Queries6049 / 7510
- Exponentiation29176 / 31023
- Exponentiation II20359 / 24087
- Counting Divisors26857 / 30185
- Common Divisors17262 / 19848
- Sum of Divisors9864 / 14346
- Divisor Analysis6760 / 8903
- Prime Multiples7878 / 9082
- Counting Coprime Pairs5224 / 5996
- Next Prime2873 / 3256
- Binomial Coefficients12611 / 13884
- Creating Strings II10431 / 10973
- Distributing Apples9950 / 10661
- Christmas Party8316 / 8847
- Permutation Order1388 / 1423
- Permutation Rounds2049 / 2245
- Bracket Sequences I5548 / 6005
- Bracket Sequences II2974 / 3371
- Counting Necklaces2708 / 2919
- Counting Grids2283 / 2417
- Fibonacci Numbers8298 / 10297
- Throwing Dice4349 / 4702
- Graph Paths I4229 / 4502
- Graph Paths II3547 / 3710
- System of Linear Equations698 / 751
- Sum of Four Squares1000 / 1190
- Triangle Number Sums882 / 1050
- Dice Probability3717 / 3986
- Moving Robots1935 / 2035
- Candy Lottery2065 / 3729
- Inversion Probability626 / 2736
- Stick Game4257 / 4354
- Nim Game I5675 / 5880
- Nim Game II4498 / 4669
- Stair Game3059 / 3308
- Grundy's Game2141 / 2799
- Another Game2420 / 2595
String Algorithms
- Word Combinations7377 / 10382
- String Matching13939 / 18380
- Finding Borders10288 / 11170
- Finding Periods7375 / 8277
- Minimal Rotation3695 / 5344
- Longest Palindrome5409 / 6979
- All Palindromes1050 / 1167
- Required Substring2070 / 3054
- Palindrome Queries2537 / 2918
- Finding Patterns2440 / 3342
- Counting Patterns2310 / 2793
- Pattern Positions1954 / 2333
- Distinct Substrings2166 / 2555
- Distinct Subsequences1401 / 1478
- Repeating Substring2323 / 2654
- String Functions2035 / 2127
- Inverse Suffix Array398 / 452
- String Transform705 / 831
- Substring Order I1475 / 1624
- Substring Order II1004 / 1276
- Substring Distribution1373 / 1481
Geometry
- Point Location Test8775 / 9714
- Line Segment Intersection5209 / 6450
- Polygon Area5960 / 6275
- Point in Polygon3356 / 4199
- Polygon Lattice Points2713 / 2897
- Minimum Euclidean Distance2406 / 3342
- Convex Hull4001 / 4721
- Maximum Manhattan Distances914 / 950
- All Manhattan Distances960 / 1054
- Intersection Points2398 / 2583
- Line Segments Trace I490 / 507
- Line Segments Trace II410 / 429
- Lines and Queries I534 / 559
- Lines and Queries II480 / 501
- Area of Rectangles1417 / 1571
- Robot Path395 / 707
Advanced Techniques
- Meet in the Middle8536 / 11409
- Hamming Distance3742 / 4081
- Corner Subgrid Check361 / 739
- Corner Subgrid Count2530 / 2881
- Reachable Nodes2653 / 2838
- Reachability Queries1785 / 2088
- Cut and Paste1833 / 2020
- Substring Reversals1618 / 1743
- Reversals and Sums1647 / 1757
- Necessary Roads2387 / 2447
- Necessary Cities2216 / 2310
- Eulerian Subgraphs940 / 989
- Monster Game I1423 / 1572
- Monster Game II1250 / 1333
- Subarray Squares1779 / 2056
- Houses and Schools965 / 1137
- Knuth Division1148 / 1287
- Apples and Bananas1350 / 1457
- One Bit Positions1017 / 1105
- Signal Processing1011 / 1080
- New Roads Queries2692 / 3217
- Dynamic Connectivity1233 / 1374
- Parcel Delivery977 / 1063
- Task Assignment1125 / 1211
- Distinct Routes II745 / 837
Sliding Window Problems
- Sliding Window Sum8431 / 8702
- Sliding Window Minimum6345 / 7210
- Sliding Window Xor6221 / 6299
- Sliding Window Or2807 / 4626
- Sliding Window Distinct Values4459 / 5157
- Sliding Window Mode3448 / 3645
- Sliding Window Mex3258 / 3425
- Sliding Window Median15463 / 17550
- Sliding Window Cost10096 / 11588
- Sliding Window Inversions1749 / 1847
- Sliding Window Advertisement338 / 525
Interactive Problems
- Hidden Integer3013 / 3145
- Hidden Permutation1360 / 1568
- K-th Highest Score623 / 750
- Permuted Binary Strings726 / 745
- Colored Chairs681 / 723
- Inversion Sorting403 / 451
Bitwise Operations
- Counting Bits6467 / 8278
- Maximum Xor Subarray3814 / 4356
- Maximum Xor Subset1471 / 1617
- Number of Subset Xors1279 / 1309
- K Subset Xors669 / 781
- All Subarray Xors406 / 627
- Xor Pyramid Peak2527 / 3018
- Xor Pyramid Diagonal462 / 517
- Xor Pyramid Row396 / 462
- SOS Bit Problem2661 / 2815
- And Subset Count655 / 680
Construction Problems
- Inverse Inversions2135 / 2279
- Monotone Subsequences1288 / 1522
- Third Permutation579 / 710
- Permutation Prime Sums582 / 624
- Chess Tournament1416 / 1627
- Distinct Sums Grid210 / 311
- Filling Trominos317 / 541
- Grid Path Construction175 / 505
Advanced Graph Problems
- Nearest Shops1029 / 1311
- Prüfer Code1769 / 1892
- Tree Traversals1454 / 1589
- Course Schedule II2433 / 3397
- Acyclic Graph Edges2514 / 2661
- Strongly Connected Edges1851 / 2139
- Even Outdegree Edges1615 / 1875
- Graph Girth4074 / 4587
- Fixed Length Walk Queries505 / 557
- Transfer Speeds Sum566 / 584
- MST Edge Check934 / 1007
- MST Edge Set Check393 / 440
- MST Edge Cost549 / 571
- Network Breakdown1376 / 1491
- Tree Coin Collecting I487 / 525
- Tree Coin Collecting II282 / 320
- Tree Isomorphism I1256 / 1477
- Tree Isomorphism II1038 / 1186
- Flight Route Requests595 / 736
- Critical Cities518 / 774
- Visiting Cities789 / 1024
- Graph Coloring313 / 364
- Bus Companies364 / 374
- Split into Two Paths145 / 245
- Network Renovation1058 / 1386
- Forbidden Cities1009 / 1293
- Creating Offices491 / 633
- New Flight Routes420 / 1063
Counting Problems
- Filled Subgrid Count I841 / 935
- Filled Subgrid Count II456 / 558
- All Letter Subgrid Count I261 / 369
- All Letter Subgrid Count II165 / 242
- Border Subgrid Count I134 / 226
- Border Subgrid Count II149 / 171
- Raab Game II152 / 172
- Empty String1968 / 2379
- Permutation Inversions1155 / 1272
- Counting Bishops460 / 512
- Counting Sequences783 / 838
- Grid Paths II868 / 1093
- Counting Permutations1003 / 1128
- Grid Completion271 / 338
- Counting Reorders309 / 424
- Tournament Graph Distribution154 / 164
- Collecting Numbers Distribution159 / 167
- Functional Graph Distribution286 / 348
Additional Problems I
- Shortest Subsequence3329 / 4329
- Distinct Values Sum902 / 926
- Distinct Values Splits641 / 686
- Swap Game2297 / 2925
- Beautiful Permutation II807 / 1230
- Multiplication Table7953 / 8821
- Bubble Sort Rounds I588 / 662
- Bubble Sort Rounds II407 / 451
- Nearest Campsites I253 / 296
- Nearest Campsites II246 / 264
- Advertisement4999 / 5280
- Special Substrings1109 / 1213
- Counting LCM Arrays395 / 427
- Square Subsets306 / 337
- Subarray Sum Constraints631 / 670
- Water Containers Moves245 / 259
- Water Containers Queries281 / 295
- Stack Weights666 / 793
- Maximum Average Subarrays238 / 262
- Subsets with Fixed Average286 / 310
- Two Array Average286 / 317
- Pyramid Array896 / 1078
- Permutation Subsequence331 / 344
- Bit Inversions2625 / 2945
- Writing Numbers827 / 893
- Letter Pair Move Game241 / 332
- Maximum Building I2333 / 2434
- Sorting Methods863 / 920
- Cyclic Array1414 / 1591
- List of Sums555 / 715
Additional Problems II
- Bouncing Ball Steps339 / 372
- Bouncing Ball Cycle142 / 192
- Knight Moves Queries175 / 209
- K Subset Sums I274 / 338
- K Subset Sums II164 / 202
- Increasing Array II936 / 1067
- Food Division590 / 700
- Swap Round Sorting461 / 571
- Binary Subsequences329 / 470
- School Excursion1556 / 1645
- Coin Grid1060 / 1224
- Grid Coloring II182 / 235
- Programmers and Artists577 / 795
- Removing Digits II251 / 526
- Coin Arrangement384 / 505
- Replace with Difference187 / 219
- Grid Puzzle I625 / 683
- Grid Puzzle II609 / 664
- Bit Substrings458 / 550
- Reversal Sorting403 / 484
- Book Shop II1466 / 1668
- GCD Subsets544 / 560
- Minimum Cost Pairs189 / 234
- Same Sum Subsets165 / 314
- Mex Grid Queries948 / 1104
- Maximum Building II501 / 613
- Stick Divisions4226 / 4921
- Stick Difference113 / 351
- Coding Company1695 / 2206
- Two Stacks Sorting219 / 658