General
Introductory Problems
- Weird Algorithm156947 / 164224
- Missing Number135369 / 141828
- Repetitions117866 / 122552
- Increasing Array110809 / 114707
- Permutations97507 / 100446
- Number Spiral68916 / 75039
- Two Knights52735 / 54385
- Two Sets57346 / 61673
- Bit Strings65602 / 69224
- Trailing Zeros61050 / 64895
- Coin Piles54067 / 59102
- Palindrome Reorder50298 / 53082
- Gray Code33701 / 37834
- Tower of Hanoi31275 / 32524
- Creating Strings42414 / 43512
- Apple Division42615 / 48122
- Chessboard and Queens25699 / 26160
- Raab Game I4825 / 5472
- Mex Grid Construction4686 / 4964
- Knight Moves Grid4643 / 4751
- Grid Coloring I3912 / 4045
- Digit Queries18094 / 21007
- String Reorder3600 / 4174
- Grid Path Description10044 / 13027
Sorting and Searching
- Distinct Numbers77403 / 83630
- Apartments57698 / 63978
- Ferris Wheel55347 / 59648
- Concert Tickets44387 / 51624
- Restaurant Customers45181 / 48730
- Movie Festival43536 / 46099
- Sum of Two Values50744 / 56734
- Maximum Subarray Sum48925 / 51068
- Stick Lengths43673 / 45664
- Missing Coin Sum32983 / 34179
- Collecting Numbers33889 / 36253
- Collecting Numbers II14218 / 18137
- Playlist33817 / 38563
- Towers33992 / 36400
- Traffic Lights26382 / 29491
- Distinct Values Subarrays6454 / 7606
- Distinct Values Subsequences4982 / 5527
- Josephus Problem I20219 / 22269
- Josephus Problem II10934 / 15089
- Nested Ranges Check11701 / 13443
- Nested Ranges Count7879 / 9304
- Room Allocation19812 / 22718
- Factory Machines28367 / 30863
- Tasks and Deadlines22751 / 23239
- Reading Books18446 / 19757
- Sum of Three Values27011 / 29897
- Sum of Four Values16780 / 18668
- Nearest Smaller Values22522 / 23298
- Subarray Sums I29875 / 31843
- Subarray Sums II27133 / 32168
- Subarray Divisibility24648 / 26836
- Distinct Values Subarrays II14834 / 16301
- Array Division23342 / 24556
- Movie Festival II12481 / 15040
- Maximum Subarray Sum II11581 / 13817
Dynamic Programming
- Dice Combinations80481 / 85105
- Minimizing Coins69552 / 74684
- Coin Combinations I63534 / 68739
- Coin Combinations II53665 / 60681
- Removing Digits59748 / 60962
- Grid Paths I56191 / 57782
- Book Shop50274 / 55251
- Array Description36925 / 40974
- Counting Towers22542 / 23893
- Edit Distance37120 / 39168
- Longest Common Subsequence9457 / 9802
- Rectangle Cutting30655 / 33455
- Minimal Grid Path4059 / 7399
- Money Sums36348 / 37717
- Removal Game21657 / 29001
- Two Sets II28574 / 30752
- Mountain Range2837 / 5216
- Increasing Subsequence29270 / 32858
- Projects20166 / 22522
- Elevator Rides12921 / 16252
- Counting Tilings7547 / 8228
- Counting Numbers10588 / 11933
- Increasing Subsequence II4387 / 5093
Graph Algorithms
- Counting Rooms55237 / 58022
- Labyrinth38331 / 45856
- Building Roads48134 / 49876
- Message Route41427 / 43071
- Building Teams39125 / 41224
- Round Trip31033 / 33777
- Monsters21301 / 25085
- Shortest Routes I33893 / 37356
- Shortest Routes II27609 / 30923
- High Score16886 / 23769
- Flight Discount21782 / 25442
- Cycle Finding15540 / 19027
- Flight Routes15082 / 16821
- Round Trip II17102 / 19188
- Course Schedule22528 / 23785
- Longest Flight Route15872 / 19666
- Game Routes17736 / 18982
- Investigation13152 / 14126
- Planets Queries I11533 / 13473
- Planets Queries II4187 / 5294
- Planets Cycles7061 / 7877
- Road Reparation17275 / 17998
- Road Construction18961 / 19549
- Flight Routes Check15360 / 16643
- Planets and Kingdoms12256 / 12753
- Giant Pizza5147 / 5654
- Coin Collector8038 / 8897
- Mail Delivery6673 / 7300
- De Bruijn Sequence3508 / 3670
- Teleporters Path5074 / 5797
- Hamiltonian Flights7649 / 8728
- Knight's Tour2879 / 3476
- Download Speed5076 / 6795
- Police Chase4072 / 4565
- School Dance4453 / 4703
- Distinct Routes3157 / 4124
Range Queries
- Static Range Sum Queries38592 / 40295
- Static Range Minimum Queries26765 / 28659
- Dynamic Range Sum Queries27751 / 28966
- Dynamic Range Minimum Queries25144 / 25732
- Range Xor Queries25996 / 26337
- Range Update Queries20660 / 22132
- Forest Queries21315 / 22103
- Hotel Queries15009 / 15921
- List Removals12457 / 13097
- Salary Queries9387 / 11805
- Prefix Sum Queries8013 / 8666
- Pizzeria Queries6434 / 6671
- Visible Buildings Queries1538 / 1681
- Range Interval Queries1197 / 1601
- Subarray Sum Queries7611 / 8245
- Subarray Sum Queries II1680 / 1742
- Distinct Values Queries7073 / 8708
- Distinct Values Queries II980 / 1123
- Increasing Array Queries2718 / 3111
- Movie Festival Queries1401 / 1558
- Forest Queries II4534 / 4879
- Range Updates and Sums6120 / 7250
- Polynomial Queries4470 / 5235
- Range Queries and Copies3234 / 3458
- Missing Coin Sum Queries709 / 933
Tree Algorithms
- Subordinates31770 / 33964
- Tree Matching18061 / 20992
- Tree Diameter25897 / 27436
- Tree Distances I19801 / 21262
- Tree Distances II16219 / 16905
- Company Queries I18011 / 18937
- Company Queries II16929 / 17749
- Distance Queries15353 / 16451
- Counting Paths9648 / 10219
- Subtree Queries11562 / 12326
- Path Queries9262 / 9814
- Path Queries II3770 / 5683
- Distinct Colors8908 / 9820
- Finding a Centroid7220 / 7511
- Fixed-Length Paths I3475 / 4482
- Fixed-Length Paths II1642 / 2984
Mathematics
- Josephus Queries4955 / 6242
- Exponentiation25206 / 26903
- Exponentiation II17677 / 21153
- Counting Divisors22965 / 25928
- Common Divisors14895 / 17266
- Sum of Divisors8321 / 12449
- Divisor Analysis5712 / 7652
- Prime Multiples6614 / 7715
- Counting Coprime Pairs4328 / 5036
- Next Prime1853 / 2124
- Binomial Coefficients10628 / 11781
- Creating Strings II8918 / 9406
- Distributing Apples8556 / 9195
- Christmas Party6956 / 7453
- Permutation Order884 / 903
- Permutation Rounds1144 / 1274
- Bracket Sequences I4724 / 5141
- Bracket Sequences II2484 / 2840
- Counting Necklaces2278 / 2464
- Counting Grids1885 / 2008
- Fibonacci Numbers7204 / 9030
- Throwing Dice3746 / 4073
- Graph Paths I3580 / 3838
- Graph Paths II2983 / 3125
- System of Linear Equations418 / 462
- Sum of Four Squares637 / 759
- Triangle Number Sums550 / 674
- Dice Probability3222 / 3474
- Moving Robots1655 / 1750
- Candy Lottery1537 / 3131
- Inversion Probability402 / 2349
- Stick Game3652 / 3741
- Nim Game I4836 / 5015
- Nim Game II3833 / 3984
- Stair Game2600 / 2827
- Grundy's Game1801 / 2358
- Another Game2028 / 2186
String Algorithms
- Word Combinations6130 / 8873
- String Matching11886 / 15863
- Finding Borders8674 / 9486
- Finding Periods6162 / 6996
- Minimal Rotation2997 / 4541
- Longest Palindrome4524 / 5991
- All Palindromes600 / 684
- Required Substring1725 / 2622
- Palindrome Queries2115 / 2457
- Finding Patterns1978 / 2807
- Counting Patterns1870 / 2324
- Pattern Positions1565 / 1912
- Distinct Substrings1783 / 2129
- Distinct Subsequences1121 / 1193
- Repeating Substring1923 / 2235
- String Functions1679 / 1759
- Inverse Suffix Array222 / 262
- String Transform548 / 664
- Substring Order I1212 / 1355
- Substring Order II799 / 1041
- Substring Distribution1126 / 1224
Geometry
- Point Location Test7630 / 8503
- Line Segment Intersection4524 / 5665
- Polygon Area5231 / 5533
- Point in Polygon2882 / 3672
- Polygon Lattice Points2442 / 2523
- Minimum Euclidean Distance2063 / 2956
- Convex Hull3486 / 4170
- Maximum Manhattan Distances581 / 599
- All Manhattan Distances570 / 623
- Intersection Points2045 / 2205
- Line Segments Trace I312 / 322
- Line Segments Trace II257 / 270
- Lines and Queries I356 / 369
- Lines and Queries II308 / 318
- Area of Rectangles1180 / 1318
- Robot Path316 / 580
Advanced Techniques
- Meet in the Middle6919 / 9578
- Hamming Distance3318 / 3615
- Corner Subgrid Check312 / 482
- Corner Subgrid Count2288 / 2569
- Reachable Nodes2335 / 2511
- Reachability Queries1548 / 1827
- Cut and Paste1562 / 1738
- Substring Reversals1371 / 1490
- Reversals and Sums1382 / 1486
- Necessary Roads1992 / 2045
- Necessary Cities1847 / 1933
- Eulerian Subgraphs815 / 858
- Monster Game I1182 / 1313
- Monster Game II1054 / 1129
- Subarray Squares1449 / 1709
- Houses and Schools791 / 946
- Knuth Division972 / 1096
- Apples and Bananas1098 / 1192
- One Bit Positions869 / 949
- Signal Processing824 / 883
- New Roads Queries2254 / 2731
- Dynamic Connectivity1032 / 1161
- Parcel Delivery797 / 881
- Task Assignment940 / 1001
- Distinct Routes II601 / 686
Sliding Window Problems
- Sliding Window Sum5048 / 5240
- Sliding Window Minimum3777 / 4327
- Sliding Window Xor3699 / 3746
- Sliding Window Or1627 / 2832
- Sliding Window Distinct Values2464 / 3104
- Sliding Window Mode2077 / 2193
- Sliding Window Mex1917 / 2020
- Sliding Window Median13939 / 15913
- Sliding Window Cost9133 / 10547
- Sliding Window Inversions1072 / 1142
- Sliding Window Advertisement207 / 329
Interactive Problems
- Hidden Integer2039 / 2112
- Hidden Permutation859 / 1009
- K-th Highest Score377 / 463
- Permuted Binary Strings468 / 480
- Colored Chairs425 / 448
- Inversion Sorting245 / 272
Bitwise Operations
- Counting Bits5003 / 6451
- Maximum Xor Subarray2979 / 3382
- Maximum Xor Subset924 / 1010
- Number of Subset Xors817 / 835
- K Subset Xors413 / 488
- All Subarray Xors252 / 415
- Xor Pyramid Peak2044 / 2482
- Xor Pyramid Diagonal291 / 327
- Xor Pyramid Row240 / 286
- SOS Bit Problem2146 / 2282
- And Subset Count383 / 395
Construction Problems
- Inverse Inversions1590 / 1692
- Monotone Subsequences976 / 1148
- Third Permutation368 / 440
- Permutation Prime Sums366 / 395
- Chess Tournament1203 / 1387
- Distinct Sums Grid112 / 174
- Filling Trominos236 / 421
- Grid Path Construction119 / 429
Advanced Graph Problems
- Nearest Shops635 / 825
- Prüfer Code1529 / 1647
- Tree Traversals1231 / 1354
- Course Schedule II1916 / 2745
- Acyclic Graph Edges2224 / 2360
- Strongly Connected Edges1586 / 1757
- Even Outdegree Edges1345 / 1571
- Graph Girth3419 / 3892
- Fixed Length Walk Queries330 / 361
- Transfer Speeds Sum377 / 388
- MST Edge Check553 / 602
- MST Edge Set Check209 / 239
- MST Edge Cost339 / 353
- Network Breakdown1026 / 1089
- Tree Coin Collecting I295 / 325
- Tree Coin Collecting II159 / 186
- Tree Isomorphism I1092 / 1307
- Tree Isomorphism II899 / 1040
- Flight Route Requests489 / 599
- Critical Cities417 / 647
- Visiting Cities671 / 893
- Graph Coloring208 / 244
- Bus Companies239 / 246
- Split into Two Paths81 / 150
- Network Renovation940 / 1249
- Forbidden Cities830 / 1084
- Creating Offices412 / 537
- New Flight Routes322 / 869
Counting Problems
- Filled Subgrid Count I515 / 574
- Filled Subgrid Count II274 / 339
- All Letter Subgrid Count I150 / 231
- All Letter Subgrid Count II114 / 145
- Border Subgrid Count I85 / 146
- Border Subgrid Count II87 / 104
- Raab Game II96 / 111
- Empty String1630 / 1988
- Permutation Inversions1020 / 1126
- Counting Bishops385 / 430
- Counting Sequences648 / 702
- Grid Paths II740 / 927
- Counting Permutations875 / 990
- Grid Completion224 / 284
- Counting Reorders235 / 343
- Tournament Graph Distribution96 / 101
- Collecting Numbers Distribution104 / 111
- Functional Graph Distribution236 / 293
Additional Problems I
- Shortest Subsequence2990 / 3943
- Distinct Values Sum589 / 610
- Distinct Values Splits423 / 448
- Swap Game2066 / 2610
- Beautiful Permutation II443 / 674
- Multiplication Table6757 / 7527
- Bubble Sort Rounds I354 / 403
- Bubble Sort Rounds II230 / 262
- Nearest Campsites I160 / 186
- Nearest Campsites II157 / 168
- Advertisement4344 / 4600
- Special Substrings974 / 1069
- Counting LCM Arrays242 / 267
- Square Subsets197 / 221
- Subarray Sum Constraints318 / 340
- Water Containers Moves151 / 158
- Water Containers Queries183 / 190
- Stack Weights579 / 691
- Maximum Average Subarrays147 / 163
- Subsets with Fixed Average182 / 198
- Two Array Average174 / 196
- Pyramid Array732 / 893
- Permutation Subsequence216 / 220
- Bit Inversions2304 / 2612
- Writing Numbers729 / 789
- Letter Pair Move Game198 / 276
- Maximum Building I2060 / 2150
- Sorting Methods759 / 813
- Cyclic Array1183 / 1345
- List of Sums480 / 629
Additional Problems II
- Bouncing Ball Steps202 / 223
- Bouncing Ball Cycle83 / 119
- Knight Moves Queries103 / 126
- K Subset Sums I160 / 211
- K Subset Sums II86 / 115
- Increasing Array II784 / 902
- Food Division506 / 613
- Swap Round Sorting410 / 507
- Binary Subsequences287 / 422
- School Excursion1367 / 1450
- Coin Grid871 / 1019
- Grid Coloring II117 / 155
- Programmers and Artists487 / 684
- Removing Digits II212 / 467
- Coin Arrangement323 / 435
- Replace with Difference119 / 141
- Grid Puzzle I525 / 578
- Grid Puzzle II501 / 554
- Bit Substrings383 / 466
- Reversal Sorting347 / 423
- Book Shop II1219 / 1393
- GCD Subsets372 / 383
- Minimum Cost Pairs119 / 155
- Same Sum Subsets103 / 190
- Mex Grid Queries833 / 978
- Maximum Building II442 / 546
- Stick Divisions3786 / 4446
- Stick Difference49 / 216
- Coding Company1471 / 1937
- Two Stacks Sorting171 / 558