General
Introductory Problems
- Weird Algorithm163608 / 171110
- Missing Number141223 / 147852
- Repetitions122821 / 127612
- Increasing Array115613 / 119601
- Permutations101513 / 104515
- Number Spiral71813 / 78098
- Two Knights55102 / 56799
- Two Sets59957 / 64356
- Bit Strings68539 / 72256
- Trailing Zeros63585 / 67549
- Coin Piles56415 / 61559
- Palindrome Reorder52462 / 55312
- Gray Code35462 / 39709
- Tower of Hanoi32943 / 34242
- Creating Strings44265 / 45381
- Apple Division44676 / 50329
- Chessboard and Queens26987 / 27465
- Raab Game I5766 / 6547
- Mex Grid Construction5615 / 5929
- Knight Moves Grid5642 / 5766
- Grid Coloring I4726 / 4890
- Digit Queries19018 / 21986
- String Reorder4280 / 4953
- Grid Path Description10558 / 13653
Sorting and Searching
- Distinct Numbers80914 / 87307
- Apartments60419 / 66796
- Ferris Wheel57975 / 62326
- Concert Tickets46494 / 53935
- Restaurant Customers47303 / 50946
- Movie Festival45751 / 48375
- Sum of Two Values53257 / 59444
- Maximum Subarray Sum51161 / 53371
- Stick Lengths45712 / 47761
- Missing Coin Sum34665 / 35903
- Collecting Numbers35512 / 37922
- Collecting Numbers II15107 / 19126
- Playlist35501 / 40417
- Towers35537 / 38022
- Traffic Lights27604 / 30810
- Distinct Values Subarrays7733 / 8933
- Distinct Values Subsequences5908 / 6518
- Josephus Problem I21226 / 23316
- Josephus Problem II11538 / 15861
- Nested Ranges Check12440 / 14212
- Nested Ranges Count8366 / 9837
- Room Allocation20792 / 23781
- Factory Machines30002 / 32573
- Tasks and Deadlines23967 / 24464
- Reading Books19398 / 20762
- Sum of Three Values28303 / 31265
- Sum of Four Values17605 / 19527
- Nearest Smaller Values23644 / 24446
- Subarray Sums I31357 / 33381
- Subarray Sums II28527 / 33703
- Subarray Divisibility25823 / 28064
- Distinct Values Subarrays II15657 / 17131
- Array Division24508 / 25753
- Movie Festival II13149 / 15820
- Maximum Subarray Sum II12222 / 14529
Dynamic Programming
- Dice Combinations84231 / 89039
- Minimizing Coins72827 / 78130
- Coin Combinations I66572 / 71918
- Coin Combinations II56335 / 63551
- Removing Digits62630 / 63879
- Grid Paths I58935 / 60571
- Book Shop52793 / 57918
- Array Description38886 / 43081
- Counting Towers23794 / 25198
- Edit Distance38933 / 41075
- Longest Common Subsequence11095 / 11501
- Rectangle Cutting32086 / 34985
- Minimal Grid Path4894 / 8625
- Money Sums37955 / 39369
- Removal Game22920 / 30296
- Two Sets II29848 / 32063
- Mountain Range3401 / 6114
- Increasing Subsequence30478 / 34189
- Projects21169 / 23606
- Elevator Rides13597 / 17017
- Counting Tilings7979 / 8678
- Counting Numbers11411 / 12785
- Increasing Subsequence II4986 / 5799
Graph Algorithms
- Counting Rooms58195 / 61065
- Labyrinth40577 / 48292
- Building Roads50728 / 52532
- Message Route43736 / 45439
- Building Teams41310 / 43485
- Round Trip32646 / 35477
- Monsters22660 / 26528
- Shortest Routes I36024 / 39578
- Shortest Routes II29096 / 32528
- High Score17986 / 24988
- Flight Discount23257 / 27067
- Cycle Finding16427 / 19989
- Flight Routes15940 / 17751
- Round Trip II17984 / 20139
- Course Schedule23955 / 25248
- Longest Flight Route17070 / 20942
- Game Routes18871 / 20147
- Investigation14072 / 15092
- Planets Queries I12187 / 14237
- Planets Queries II4435 / 5584
- Planets Cycles7452 / 8298
- Road Reparation18502 / 19272
- Road Construction20358 / 21006
- Flight Routes Check16143 / 17460
- Planets and Kingdoms13007 / 13525
- Giant Pizza5457 / 5989
- Coin Collector8544 / 9423
- Mail Delivery7009 / 7654
- De Bruijn Sequence3707 / 3878
- Teleporters Path5377 / 6113
- Hamiltonian Flights8124 / 9240
- Knight's Tour3086 / 3725
- Download Speed5388 / 7145
- Police Chase4303 / 4812
- School Dance4728 / 4993
- Distinct Routes3335 / 4336
Range Queries
- Static Range Sum Queries40714 / 42533
- Static Range Minimum Queries28226 / 30217
- Dynamic Range Sum Queries29296 / 30580
- Dynamic Range Minimum Queries26506 / 27136
- Range Xor Queries27291 / 27664
- Range Update Queries21785 / 23325
- Forest Queries22322 / 23122
- Hotel Queries15830 / 16760
- List Removals13134 / 13789
- Salary Queries9967 / 12483
- Prefix Sum Queries8472 / 9143
- Pizzeria Queries6810 / 7054
- Visible Buildings Queries1798 / 1962
- Range Interval Queries1388 / 1866
- Subarray Sum Queries7959 / 8612
- Subarray Sum Queries II2010 / 2079
- Distinct Values Queries7487 / 9159
- Distinct Values Queries II1164 / 1323
- Increasing Array Queries2878 / 3288
- Movie Festival Queries1531 / 1696
- Forest Queries II4744 / 5093
- Range Updates and Sums6489 / 7662
- Polynomial Queries4798 / 5634
- Range Queries and Copies3410 / 3640
- Missing Coin Sum Queries791 / 1031
Tree Algorithms
- Subordinates33259 / 35584
- Tree Matching18957 / 21968
- Tree Diameter27138 / 28741
- Tree Distances I20819 / 22354
- Tree Distances II16984 / 17767
- Company Queries I18942 / 19931
- Company Queries II17729 / 18658
- Distance Queries16033 / 17193
- Counting Paths10081 / 10667
- Subtree Queries12090 / 12867
- Path Queries9725 / 10287
- Path Queries II4061 / 6037
- Distinct Colors9377 / 10308
- Finding a Centroid7569 / 7872
- Fixed-Length Paths I3726 / 4747
- Fixed-Length Paths II1772 / 3178
Mathematics
- Josephus Queries5246 / 6605
- Exponentiation26362 / 28105
- Exponentiation II18474 / 22026
- Counting Divisors24069 / 27137
- Common Divisors15562 / 17992
- Sum of Divisors8764 / 12994
- Divisor Analysis6017 / 8013
- Prime Multiples6984 / 8125
- Counting Coprime Pairs4614 / 5338
- Next Prime2166 / 2482
- Binomial Coefficients11225 / 12421
- Creating Strings II9354 / 9862
- Distributing Apples8917 / 9579
- Christmas Party7332 / 7841
- Permutation Order1034 / 1057
- Permutation Rounds1439 / 1602
- Bracket Sequences I4958 / 5392
- Bracket Sequences II2620 / 2991
- Counting Necklaces2404 / 2598
- Counting Grids2003 / 2127
- Fibonacci Numbers7480 / 9348
- Throwing Dice3905 / 4240
- Graph Paths I3767 / 4029
- Graph Paths II3148 / 3296
- System of Linear Equations520 / 568
- Sum of Four Squares758 / 888
- Triangle Number Sums648 / 785
- Dice Probability3339 / 3595
- Moving Robots1737 / 1834
- Candy Lottery1671 / 3287
- Inversion Probability475 / 2441
- Stick Game3809 / 3899
- Nim Game I5085 / 5268
- Nim Game II4018 / 4175
- Stair Game2739 / 2970
- Grundy's Game1900 / 2489
- Another Game2149 / 2311
String Algorithms
- Word Combinations6466 / 9265
- String Matching12456 / 16577
- Finding Borders9140 / 9980
- Finding Periods6492 / 7340
- Minimal Rotation3172 / 4756
- Longest Palindrome4758 / 6249
- All Palindromes711 / 808
- Required Substring1840 / 2758
- Palindrome Queries2238 / 2606
- Finding Patterns2113 / 2959
- Counting Patterns2000 / 2464
- Pattern Positions1684 / 2044
- Distinct Substrings1900 / 2256
- Distinct Subsequences1202 / 1277
- Repeating Substring2052 / 2371
- String Functions1796 / 1881
- Inverse Suffix Array274 / 321
- String Transform595 / 715
- Substring Order I1304 / 1448
- Substring Order II865 / 1122
- Substring Distribution1207 / 1309
Geometry
- Point Location Test7969 / 8873
- Line Segment Intersection4722 / 5905
- Polygon Area5445 / 5751
- Point in Polygon3008 / 3818
- Polygon Lattice Points2532 / 2615
- Minimum Euclidean Distance2183 / 3087
- Convex Hull3660 / 4361
- Maximum Manhattan Distances661 / 684
- All Manhattan Distances655 / 713
- Intersection Points2155 / 2324
- Line Segments Trace I358 / 372
- Line Segments Trace II297 / 314
- Lines and Queries I411 / 429
- Lines and Queries II356 / 368
- Area of Rectangles1242 / 1387
- Robot Path332 / 618
Advanced Techniques
- Meet in the Middle7241 / 9953
- Hamming Distance3421 / 3742
- Corner Subgrid Check368 / 561
- Corner Subgrid Count2366 / 2661
- Reachable Nodes2439 / 2621
- Reachability Queries1631 / 1918
- Cut and Paste1666 / 1845
- Substring Reversals1452 / 1574
- Reversals and Sums1474 / 1579
- Necessary Roads2136 / 2192
- Necessary Cities1988 / 2079
- Eulerian Subgraphs860 / 904
- Monster Game I1258 / 1398
- Monster Game II1114 / 1191
- Subarray Squares1571 / 1836
- Houses and Schools846 / 1011
- Knuth Division1028 / 1158
- Apples and Bananas1177 / 1276
- One Bit Positions913 / 995
- Signal Processing877 / 938
- New Roads Queries2382 / 2879
- Dynamic Connectivity1096 / 1233
- Parcel Delivery842 / 926
- Task Assignment976 / 1050
- Distinct Routes II637 / 724
Sliding Window Problems
- Sliding Window Sum6093 / 6319
- Sliding Window Minimum4542 / 5188
- Sliding Window Xor4461 / 4523
- Sliding Window Or1976 / 3365
- Sliding Window Distinct Values3057 / 3725
- Sliding Window Mode2468 / 2627
- Sliding Window Mex2276 / 2404
- Sliding Window Median14362 / 16385
- Sliding Window Cost9396 / 10832
- Sliding Window Inversions1277 / 1354
- Sliding Window Advertisement243 / 389
Interactive Problems
- Hidden Integer2416 / 2514
- Hidden Permutation1030 / 1209
- K-th Highest Score454 / 552
- Permuted Binary Strings559 / 574
- Colored Chairs508 / 536
- Inversion Sorting287 / 321
Bitwise Operations
- Counting Bits5396 / 6977
- Maximum Xor Subarray3208 / 3665
- Maximum Xor Subset1079 / 1179
- Number of Subset Xors949 / 968
- K Subset Xors479 / 570
- All Subarray Xors293 / 480
- Xor Pyramid Peak2173 / 2626
- Xor Pyramid Diagonal338 / 378
- Xor Pyramid Row290 / 341
- SOS Bit Problem2283 / 2424
- And Subset Count458 / 476
Construction Problems
- Inverse Inversions1781 / 1900
- Monotone Subsequences1074 / 1267
- Third Permutation434 / 525
- Permutation Prime Sums437 / 472
- Chess Tournament1262 / 1461
- Distinct Sums Grid139 / 215
- Filling Trominos247 / 448
- Grid Path Construction124 / 443
Advanced Graph Problems
- Nearest Shops753 / 972
- Prüfer Code1601 / 1719
- Tree Traversals1299 / 1430
- Course Schedule II2040 / 2916
- Acyclic Graph Edges2308 / 2444
- Strongly Connected Edges1585 / 1870
- Even Outdegree Edges1445 / 1682
- Graph Girth3598 / 4083
- Fixed Length Walk Queries374 / 415
- Transfer Speeds Sum439 / 453
- MST Edge Check678 / 737
- MST Edge Set Check256 / 289
- MST Edge Cost410 / 429
- Network Breakdown1227 / 1335
- Tree Coin Collecting I366 / 398
- Tree Coin Collecting II197 / 230
- Tree Isomorphism I1141 / 1355
- Tree Isomorphism II937 / 1080
- Flight Route Requests521 / 642
- Critical Cities447 / 685
- Visiting Cities713 / 937
- Graph Coloring239 / 279
- Bus Companies280 / 288
- Split into Two Paths101 / 185
- Network Renovation969 / 1287
- Forbidden Cities880 / 1149
- Creating Offices437 / 571
- New Flight Routes346 / 924
Counting Problems
- Filled Subgrid Count I614 / 688
- Filled Subgrid Count II332 / 409
- All Letter Subgrid Count I184 / 276
- All Letter Subgrid Count II145 / 186
- Border Subgrid Count I99 / 170
- Border Subgrid Count II106 / 125
- Raab Game II111 / 128
- Empty String1758 / 2137
- Permutation Inversions1069 / 1180
- Counting Bishops413 / 460
- Counting Sequences698 / 752
- Grid Paths II795 / 994
- Counting Permutations928 / 1047
- Grid Completion233 / 297
- Counting Reorders258 / 368
- Tournament Graph Distribution111 / 118
- Collecting Numbers Distribution119 / 127
- Functional Graph Distribution254 / 313
Additional Problems I
- Shortest Subsequence3094 / 4072
- Distinct Values Sum699 / 723
- Distinct Values Splits503 / 534
- Swap Game2107 / 2709
- Beautiful Permutation II568 / 860
- Multiplication Table7138 / 7951
- Bubble Sort Rounds I427 / 488
- Bubble Sort Rounds II284 / 320
- Nearest Campsites I187 / 218
- Nearest Campsites II183 / 195
- Advertisement4560 / 4831
- Special Substrings1013 / 1112
- Counting LCM Arrays285 / 311
- Square Subsets232 / 257
- Subarray Sum Constraints430 / 458
- Water Containers Moves184 / 194
- Water Containers Queries218 / 229
- Stack Weights608 / 726
- Maximum Average Subarrays179 / 197
- Subsets with Fixed Average221 / 240
- Two Array Average219 / 245
- Pyramid Array787 / 952
- Permutation Subsequence266 / 274
- Bit Inversions2412 / 2726
- Writing Numbers762 / 823
- Letter Pair Move Game210 / 290
- Maximum Building I2155 / 2247
- Sorting Methods798 / 852
- Cyclic Array1253 / 1425
- List of Sums509 / 659
Additional Problems II
- Bouncing Ball Steps240 / 266
- Bouncing Ball Cycle94 / 133
- Knight Moves Queries121 / 146
- K Subset Sums I195 / 250
- K Subset Sums II110 / 144
- Increasing Array II830 / 947
- Food Division539 / 646
- Swap Round Sorting426 / 525
- Binary Subsequences297 / 433
- School Excursion1435 / 1518
- Coin Grid925 / 1079
- Grid Coloring II143 / 185
- Programmers and Artists522 / 730
- Removing Digits II219 / 478
- Coin Arrangement343 / 457
- Replace with Difference133 / 159
- Grid Puzzle I561 / 614
- Grid Puzzle II540 / 592
- Bit Substrings411 / 497
- Reversal Sorting365 / 441
- Book Shop II1290 / 1468
- GCD Subsets422 / 434
- Minimum Cost Pairs147 / 191
- Same Sum Subsets118 / 232
- Mex Grid Queries875 / 1025
- Maximum Building II461 / 568
- Stick Divisions3923 / 4591
- Stick Difference63 / 263
- Coding Company1557 / 2036
- Two Stacks Sorting184 / 589