General
Introductory Problems
- Weird Algorithm154845 / 162058
- Missing Number133604 / 140009
- Repetitions116290 / 120954
- Increasing Array109333 / 113211
- Permutations96156 / 99079
- Number Spiral67989 / 74044
- Two Knights51977 / 53602
- Two Sets56530 / 60825
- Bit Strings64675 / 68261
- Trailing Zeros60246 / 64072
- Coin Piles53348 / 58348
- Palindrome Reorder49625 / 52372
- Gray Code33172 / 37277
- Tower of Hanoi30778 / 32013
- Creating Strings41853 / 42939
- Apple Division41979 / 47421
- Chessboard and Queens25309 / 25765
- Raab Game I4517 / 5105
- Mex Grid Construction4370 / 4637
- Knight Moves Grid4334 / 4433
- Grid Coloring I3637 / 3763
- Digit Queries17800 / 20695
- String Reorder3360 / 3903
- Grid Path Description9898 / 12854
Sorting and Searching
- Distinct Numbers76258 / 82438
- Apartments56694 / 62943
- Ferris Wheel54471 / 58754
- Concert Tickets43733 / 50898
- Restaurant Customers44494 / 48015
- Movie Festival42853 / 45390
- Sum of Two Values49914 / 55843
- Maximum Subarray Sum48177 / 50300
- Stick Lengths43005 / 44981
- Missing Coin Sum32400 / 33581
- Collecting Numbers33265 / 35613
- Collecting Numbers II13919 / 17770
- Playlist33212 / 37907
- Towers33486 / 35865
- Traffic Lights25966 / 29048
- Distinct Values Subarrays5942 / 7069
- Distinct Values Subsequences4652 / 5146
- Josephus Problem I19847 / 21875
- Josephus Problem II10742 / 14821
- Nested Ranges Check11452 / 13163
- Nested Ranges Count7720 / 9120
- Room Allocation19521 / 22384
- Factory Machines27836 / 30312
- Tasks and Deadlines22350 / 22829
- Reading Books18123 / 19410
- Sum of Three Values26590 / 29442
- Sum of Four Values16495 / 18369
- Nearest Smaller Values22106 / 22866
- Subarray Sums I29325 / 31261
- Subarray Sums II26626 / 31585
- Subarray Divisibility24234 / 26392
- Distinct Values Subarrays II14578 / 16038
- Array Division22966 / 24171
- Movie Festival II12272 / 14807
- Maximum Subarray Sum II11349 / 13548
Dynamic Programming
- Dice Combinations79288 / 83861
- Minimizing Coins68485 / 73566
- Coin Combinations I62547 / 67712
- Coin Combinations II52806 / 59767
- Removing Digits58831 / 60026
- Grid Paths I55359 / 56934
- Book Shop49481 / 54409
- Array Description36339 / 40353
- Counting Towers22164 / 23503
- Edit Distance36629 / 38655
- Longest Common Subsequence8948 / 9272
- Rectangle Cutting30254 / 33035
- Minimal Grid Path3808 / 7032
- Money Sums35849 / 37206
- Removal Game21313 / 28653
- Two Sets II28190 / 30355
- Mountain Range2690 / 4946
- Increasing Subsequence28884 / 32428
- Projects19859 / 22200
- Elevator Rides12713 / 16013
- Counting Tilings7429 / 8096
- Counting Numbers10387 / 11714
- Increasing Subsequence II4246 / 4930
Graph Algorithms
- Counting Rooms54374 / 57115
- Labyrinth37646 / 45106
- Building Roads47331 / 49041
- Message Route40748 / 42365
- Building Teams38563 / 40651
- Round Trip30614 / 33330
- Monsters20902 / 24668
- Shortest Routes I33434 / 36882
- Shortest Routes II27234 / 30521
- High Score16598 / 23436
- Flight Discount21453 / 25090
- Cycle Finding15303 / 18766
- Flight Routes14867 / 16586
- Round Trip II16903 / 18970
- Course Schedule22174 / 23423
- Longest Flight Route15634 / 19409
- Game Routes17494 / 18733
- Investigation12979 / 13949
- Planets Queries I11361 / 13286
- Planets Queries II4103 / 5195
- Planets Cycles6958 / 7773
- Road Reparation17031 / 17752
- Road Construction18676 / 19255
- Flight Routes Check15128 / 16396
- Planets and Kingdoms12069 / 12564
- Giant Pizza5056 / 5559
- Coin Collector7899 / 8755
- Mail Delivery6583 / 7202
- De Bruijn Sequence3454 / 3616
- Teleporters Path4998 / 5716
- Hamiltonian Flights7529 / 8589
- Knight's Tour2827 / 3420
- Download Speed4963 / 6656
- Police Chase3978 / 4459
- School Dance4362 / 4610
- Distinct Routes3088 / 4040
Range Queries
- Static Range Sum Queries37948 / 39639
- Static Range Minimum Queries26409 / 28273
- Dynamic Range Sum Queries27405 / 28606
- Dynamic Range Minimum Queries24826 / 25407
- Range Xor Queries25690 / 26031
- Range Update Queries20394 / 21854
- Forest Queries20973 / 21759
- Hotel Queries14802 / 15707
- List Removals12276 / 12912
- Salary Queries9219 / 11623
- Prefix Sum Queries7877 / 8529
- Pizzeria Queries6331 / 6567
- Visible Buildings Queries1457 / 1597
- Range Interval Queries1139 / 1516
- Subarray Sum Queries7526 / 8157
- Subarray Sum Queries II1583 / 1647
- Distinct Values Queries6961 / 8590
- Distinct Values Queries II916 / 1053
- Increasing Array Queries2669 / 3059
- Movie Festival Queries1359 / 1512
- Forest Queries II4476 / 4818
- Range Updates and Sums6014 / 7139
- Polynomial Queries4406 / 5163
- Range Queries and Copies3172 / 3394
- Missing Coin Sum Queries679 / 901
Tree Algorithms
- Subordinates31305 / 33468
- Tree Matching17786 / 20694
- Tree Diameter25535 / 27060
- Tree Distances I19527 / 20974
- Tree Distances II16000 / 16680
- Company Queries I17761 / 18679
- Company Queries II16696 / 17502
- Distance Queries15127 / 16222
- Counting Paths9490 / 10062
- Subtree Queries11362 / 12124
- Path Queries9121 / 9666
- Path Queries II3671 / 5568
- Distinct Colors8759 / 9669
- Finding a Centroid7081 / 7370
- Fixed-Length Paths I3382 / 4380
- Fixed-Length Paths II1592 / 2910
Mathematics
- Josephus Queries4873 / 6143
- Exponentiation24798 / 26485
- Exponentiation II17438 / 20891
- Counting Divisors22461 / 25343
- Common Divisors14691 / 17049
- Sum of Divisors8206 / 12286
- Divisor Analysis5609 / 7525
- Prime Multiples6501 / 7591
- Counting Coprime Pairs4235 / 4941
- Next Prime1760 / 2020
- Binomial Coefficients10462 / 11601
- Creating Strings II8785 / 9268
- Distributing Apples8434 / 9066
- Christmas Party6858 / 7352
- Permutation Order836 / 854
- Permutation Rounds1056 / 1171
- Bracket Sequences I4647 / 5059
- Bracket Sequences II2430 / 2784
- Counting Necklaces2237 / 2422
- Counting Grids1843 / 1967
- Fibonacci Numbers7112 / 8913
- Throwing Dice3692 / 4016
- Graph Paths I3508 / 3763
- Graph Paths II2930 / 3072
- System of Linear Equations390 / 434
- Sum of Four Squares591 / 707
- Triangle Number Sums514 / 635
- Dice Probability3173 / 3422
- Moving Robots1627 / 1722
- Candy Lottery1479 / 3064
- Inversion Probability379 / 2311
- Stick Game3581 / 3668
- Nim Game I4745 / 4926
- Nim Game II3760 / 3912
- Stair Game2542 / 2767
- Grundy's Game1759 / 2313
- Another Game1990 / 2145
String Algorithms
- Word Combinations6059 / 8776
- String Matching11728 / 15662
- Finding Borders8562 / 9367
- Finding Periods6081 / 6907
- Minimal Rotation2958 / 4490
- Longest Palindrome4474 / 5931
- All Palindromes576 / 657
- Required Substring1696 / 2590
- Palindrome Queries2087 / 2429
- Finding Patterns1949 / 2772
- Counting Patterns1843 / 2290
- Pattern Positions1543 / 1888
- Distinct Substrings1761 / 2103
- Distinct Subsequences1104 / 1177
- Repeating Substring1900 / 2210
- String Functions1654 / 1733
- Inverse Suffix Array194 / 234
- String Transform537 / 653
- Substring Order I1193 / 1335
- Substring Order II792 / 1028
- Substring Distribution1110 / 1206
Geometry
- Point Location Test7510 / 8373
- Line Segment Intersection4460 / 5589
- Polygon Area5152 / 5451
- Point in Polygon2839 / 3626
- Polygon Lattice Points2403 / 2484
- Minimum Euclidean Distance2003 / 2877
- Convex Hull3441 / 4120
- Maximum Manhattan Distances545 / 562
- All Manhattan Distances541 / 591
- Intersection Points2010 / 2169
- Line Segments Trace I298 / 307
- Line Segments Trace II244 / 257
- Lines and Queries I336 / 348
- Lines and Queries II288 / 298
- Area of Rectangles1161 / 1296
- Robot Path307 / 565
Advanced Techniques
- Meet in the Middle6817 / 9468
- Hamming Distance3277 / 3573
- Corner Subgrid Check296 / 463
- Corner Subgrid Count2271 / 2550
- Reachable Nodes2309 / 2485
- Reachability Queries1530 / 1807
- Cut and Paste1537 / 1714
- Substring Reversals1347 / 1467
- Reversals and Sums1356 / 1459
- Necessary Roads1975 / 2027
- Necessary Cities1823 / 1909
- Eulerian Subgraphs804 / 847
- Monster Game I1164 / 1295
- Monster Game II1038 / 1113
- Subarray Squares1419 / 1677
- Houses and Schools783 / 937
- Knuth Division960 / 1083
- Apples and Bananas1086 / 1181
- One Bit Positions861 / 941
- Signal Processing819 / 878
- New Roads Queries2218 / 2695
- Dynamic Connectivity1013 / 1142
- Parcel Delivery784 / 867
- Task Assignment923 / 983
- Distinct Routes II591 / 676
Sliding Window Problems
- Sliding Window Sum4686 / 4873
- Sliding Window Minimum3478 / 3986
- Sliding Window Xor3427 / 3471
- Sliding Window Or1521 / 2664
- Sliding Window Distinct Values2262 / 2902
- Sliding Window Mode1977 / 2084
- Sliding Window Mex1790 / 1888
- Sliding Window Median13782 / 15742
- Sliding Window Cost9043 / 10442
- Sliding Window Inversions1016 / 1085
- Sliding Window Advertisement200 / 319
Interactive Problems
- Hidden Integer1908 / 1973
- Hidden Permutation811 / 957
- K-th Highest Score354 / 434
- Permuted Binary Strings443 / 455
- Colored Chairs399 / 420
- Inversion Sorting229 / 252
Bitwise Operations
- Counting Bits4879 / 6295
- Maximum Xor Subarray2916 / 3310
- Maximum Xor Subset868 / 952
- Number of Subset Xors767 / 784
- K Subset Xors375 / 447
- All Subarray Xors242 / 393
- Xor Pyramid Peak1994 / 2432
- Xor Pyramid Diagonal273 / 308
- Xor Pyramid Row223 / 268
- SOS Bit Problem2099 / 2235
- And Subset Count357 / 368
Construction Problems
- Inverse Inversions1542 / 1642
- Monotone Subsequences944 / 1109
- Third Permutation344 / 410
- Permutation Prime Sums346 / 373
- Chess Tournament1183 / 1365
- Distinct Sums Grid103 / 165
- Filling Trominos233 / 418
- Grid Path Construction119 / 427
Advanced Graph Problems
- Nearest Shops607 / 784
- Prüfer Code1504 / 1620
- Tree Traversals1191 / 1311
- Course Schedule II1886 / 2706
- Acyclic Graph Edges2203 / 2339
- Strongly Connected Edges1557 / 1728
- Even Outdegree Edges1322 / 1548
- Graph Girth3362 / 3833
- Fixed Length Walk Queries315 / 345
- Transfer Speeds Sum364 / 375
- MST Edge Check525 / 569
- MST Edge Set Check195 / 225
- MST Edge Cost326 / 340
- Network Breakdown1011 / 1073
- Tree Coin Collecting I279 / 308
- Tree Coin Collecting II148 / 175
- Tree Isomorphism I1071 / 1284
- Tree Isomorphism II876 / 1018
- Flight Route Requests480 / 589
- Critical Cities403 / 626
- Visiting Cities665 / 885
- Graph Coloring203 / 239
- Bus Companies230 / 238
- Split into Two Paths77 / 146
- Network Renovation925 / 1234
- Forbidden Cities821 / 1073
- Creating Offices407 / 531
- New Flight Routes310 / 835
Counting Problems
- Filled Subgrid Count I486 / 542
- Filled Subgrid Count II259 / 320
- All Letter Subgrid Count I142 / 222
- All Letter Subgrid Count II109 / 139
- Border Subgrid Count I81 / 140
- Border Subgrid Count II83 / 100
- Raab Game II87 / 103
- Empty String1606 / 1962
- Permutation Inversions1006 / 1112
- Counting Bishops377 / 422
- Counting Sequences638 / 694
- Grid Paths II736 / 921
- Counting Permutations862 / 977
- Grid Completion218 / 277
- Counting Reorders230 / 337
- Tournament Graph Distribution91 / 96
- Collecting Numbers Distribution97 / 106
- Functional Graph Distribution235 / 291
Additional Problems I
- Shortest Subsequence2961 / 3908
- Distinct Values Sum571 / 590
- Distinct Values Splits409 / 434
- Swap Game2039 / 2581
- Beautiful Permutation II405 / 613
- Multiplication Table6629 / 7393
- Bubble Sort Rounds I338 / 384
- Bubble Sort Rounds II215 / 246
- Nearest Campsites I152 / 178
- Nearest Campsites II150 / 161
- Advertisement4259 / 4512
- Special Substrings965 / 1060
- Counting LCM Arrays227 / 249
- Square Subsets189 / 211
- Subarray Sum Constraints297 / 319
- Water Containers Moves140 / 148
- Water Containers Queries175 / 182
- Stack Weights576 / 685
- Maximum Average Subarrays144 / 160
- Subsets with Fixed Average176 / 193
- Two Array Average168 / 189
- Pyramid Array722 / 878
- Permutation Subsequence208 / 212
- Bit Inversions2287 / 2595
- Writing Numbers725 / 784
- Letter Pair Move Game196 / 275
- Maximum Building I2031 / 2121
- Sorting Methods755 / 809
- Cyclic Array1161 / 1321
- List of Sums471 / 617
Additional Problems II
- Bouncing Ball Steps191 / 212
- Bouncing Ball Cycle77 / 112
- Knight Moves Queries101 / 124
- K Subset Sums I154 / 203
- K Subset Sums II80 / 111
- Increasing Array II777 / 895
- Food Division505 / 611
- Swap Round Sorting403 / 498
- Binary Subsequences285 / 420
- School Excursion1351 / 1433
- Coin Grid858 / 1003
- Grid Coloring II115 / 153
- Programmers and Artists485 / 682
- Removing Digits II211 / 465
- Coin Arrangement321 / 433
- Replace with Difference109 / 131
- Grid Puzzle I519 / 572
- Grid Puzzle II494 / 547
- Bit Substrings379 / 462
- Reversal Sorting345 / 420
- Book Shop II1192 / 1368
- GCD Subsets356 / 365
- Minimum Cost Pairs92 / 130
- Same Sum Subsets100 / 183
- Mex Grid Queries826 / 971
- Maximum Building II437 / 539
- Stick Divisions3738 / 4392
- Stick Difference39 / 197
- Coding Company1453 / 1907
- Two Stacks Sorting171 / 547