General
Introductory Problems
- Weird Algorithm177591 / 185481
- Missing Number153241 / 160158
- Repetitions133180 / 138174
- Increasing Array125535 / 129677
- Permutations109948 / 113119
- Number Spiral78171 / 84731
- Two Knights60322 / 62091
- Two Sets65573 / 70137
- Bit Strings74548 / 78446
- Trailing Zeros69019 / 73184
- Coin Piles61423 / 66797
- Palindrome Reorder57087 / 60045
- Gray Code39032 / 43516
- Tower of Hanoi36394 / 37781
- Creating Strings48138 / 49299
- Apple Division48869 / 54738
- Chessboard and Queens29765 / 30266
- Raab Game I7861 / 8802
- Mex Grid Construction7631 / 8000
- Knight Moves Grid7701 / 7870
- Grid Coloring I6474 / 6700
- Digit Queries20901 / 23924
- String Reorder5776 / 6595
- Grid Path Description11730 / 15002
Sorting and Searching
- Distinct Numbers88404 / 95098
- Apartments66434 / 73028
- Ferris Wheel64072 / 68613
- Concert Tickets51407 / 59239
- Restaurant Customers52218 / 56036
- Movie Festival50807 / 53543
- Sum of Two Values58691 / 65188
- Maximum Subarray Sum55986 / 58263
- Stick Lengths50188 / 52321
- Missing Coin Sum38452 / 39755
- Collecting Numbers39368 / 41894
- Collecting Numbers II17352 / 21559
- Playlist39306 / 44470
- Towers39268 / 41869
- Traffic Lights30579 / 33967
- Distinct Values Subarrays10683 / 11930
- Distinct Values Subsequences8234 / 8950
- Josephus Problem I23851 / 26044
- Josephus Problem II12988 / 17767
- Nested Ranges Check14244 / 16083
- Nested Ranges Count9524 / 11123
- Room Allocation23225 / 26402
- Factory Machines33652 / 36306
- Tasks and Deadlines26853 / 27370
- Reading Books21815 / 23259
- Sum of Three Values31323 / 34394
- Sum of Four Values19580 / 21592
- Nearest Smaller Values26263 / 27097
- Subarray Sums I34837 / 36908
- Subarray Sums II31788 / 37217
- Subarray Divisibility28764 / 31105
- Distinct Values Subarrays II17604 / 19121
- Array Division27260 / 28565
- Movie Festival II14845 / 17659
- Maximum Subarray Sum II13842 / 16288
Dynamic Programming
- Dice Combinations92932 / 98039
- Minimizing Coins80371 / 86010
- Coin Combinations I73439 / 79091
- Coin Combinations II62326 / 69974
- Removing Digits69285 / 70647
- Grid Paths I65075 / 66809
- Book Shop58707 / 64136
- Array Description43537 / 47957
- Counting Towers27176 / 28673
- Edit Distance43293 / 45527
- Longest Common Subsequence15328 / 15830
- Rectangle Cutting35761 / 38827
- Minimal Grid Path7173 / 11817
- Money Sums42147 / 43625
- Removal Game26240 / 33762
- Two Sets II33321 / 35614
- Mountain Range4960 / 8441
- Increasing Subsequence33817 / 37839
- Projects23842 / 26467
- Elevator Rides15659 / 19349
- Counting Tilings9180 / 9917
- Counting Numbers13722 / 15170
- Increasing Subsequence II6215 / 7289
Graph Algorithms
- Counting Rooms64618 / 67609
- Labyrinth45992 / 53966
- Building Roads56614 / 58486
- Message Route49111 / 50877
- Building Teams46338 / 48561
- Round Trip36770 / 39730
- Monsters26176 / 30194
- Shortest Routes I40594 / 44234
- Shortest Routes II32815 / 36407
- High Score21117 / 28397
- Flight Discount27049 / 31027
- Cycle Finding19085 / 22771
- Flight Routes18605 / 20515
- Round Trip II20617 / 22865
- Course Schedule27200 / 28515
- Longest Flight Route19986 / 23995
- Game Routes21767 / 23087
- Investigation16552 / 17643
- Planets Queries I14362 / 16543
- Planets Queries II5215 / 6471
- Planets Cycles8655 / 9554
- Road Reparation21244 / 22059
- Road Construction23132 / 23822
- Flight Routes Check18379 / 19748
- Planets and Kingdoms14993 / 15603
- Giant Pizza6324 / 6899
- Coin Collector9961 / 10884
- Mail Delivery7919 / 8593
- De Bruijn Sequence4168 / 4356
- Teleporters Path6148 / 6903
- Hamiltonian Flights9398 / 10616
- Knight's Tour3508 / 4191
- Download Speed6095 / 7921
- Police Chase4870 / 5401
- School Dance5347 / 5633
- Distinct Routes3776 / 4831
Range Queries
- Static Range Sum Queries45219 / 47194
- Static Range Minimum Queries31090 / 33260
- Dynamic Range Sum Queries32344 / 33712
- Dynamic Range Minimum Queries29206 / 29880
- Range Xor Queries29818 / 30206
- Range Update Queries24141 / 25764
- Forest Queries24762 / 25603
- Hotel Queries17590 / 18555
- List Removals14643 / 15329
- Salary Queries11337 / 13990
- Prefix Sum Queries9494 / 10195
- Pizzeria Queries7574 / 7828
- Visible Buildings Queries2339 / 2536
- Range Interval Queries1785 / 2366
- Subarray Sum Queries8734 / 9415
- Subarray Sum Queries II2645 / 2723
- Distinct Values Queries8290 / 10024
- Distinct Values Queries II1477 / 1672
- Increasing Array Queries3150 / 3579
- Movie Festival Queries1764 / 1938
- Forest Queries II5138 / 5493
- Range Updates and Sums7257 / 8475
- Polynomial Queries5314 / 6189
- Range Queries and Copies3748 / 3990
- Missing Coin Sum Queries891 / 1220
Tree Algorithms
- Subordinates37201 / 39684
- Tree Matching21580 / 24808
- Tree Diameter30465 / 32141
- Tree Distances I23687 / 25296
- Tree Distances II19304 / 20147
- Company Queries I21697 / 22750
- Company Queries II20296 / 21289
- Distance Queries18302 / 19528
- Counting Paths11581 / 12205
- Subtree Queries13581 / 14417
- Path Queries10961 / 11549
- Path Queries II4607 / 6724
- Distinct Colors10496 / 11469
- Finding a Centroid8535 / 8865
- Fixed-Length Paths I4285 / 5363
- Fixed-Length Paths II2104 / 3632
Mathematics
- Josephus Queries5917 / 7365
- Exponentiation28748 / 30573
- Exponentiation II20061 / 23770
- Counting Divisors26439 / 29736
- Common Divisors16988 / 19564
- Sum of Divisors9707 / 14137
- Divisor Analysis6649 / 8765
- Prime Multiples7731 / 8926
- Counting Coprime Pairs5113 / 5881
- Next Prime2749 / 3126
- Binomial Coefficients12383 / 13643
- Creating Strings II10242 / 10777
- Distributing Apples9782 / 10490
- Christmas Party8163 / 8691
- Permutation Order1320 / 1355
- Permutation Rounds1928 / 2120
- Bracket Sequences I5450 / 5905
- Bracket Sequences II2912 / 3304
- Counting Necklaces2634 / 2843
- Counting Grids2218 / 2352
- Fibonacci Numbers8078 / 10035
- Throwing Dice4271 / 4619
- Graph Paths I4145 / 4414
- Graph Paths II3476 / 3638
- System of Linear Equations671 / 725
- Sum of Four Squares947 / 1132
- Triangle Number Sums831 / 993
- Dice Probability3659 / 3927
- Moving Robots1900 / 2000
- Candy Lottery1993 / 3656
- Inversion Probability599 / 2694
- Stick Game4172 / 4269
- Nim Game I5578 / 5780
- Nim Game II4414 / 4583
- Stair Game2993 / 3240
- Grundy's Game2091 / 2735
- Another Game2368 / 2542
String Algorithms
- Word Combinations7229 / 10206
- String Matching13704 / 18054
- Finding Borders10110 / 10988
- Finding Periods7232 / 8130
- Minimal Rotation3615 / 5259
- Longest Palindrome5320 / 6883
- All Palindromes993 / 1108
- Required Substring2032 / 3003
- Palindrome Queries2485 / 2863
- Finding Patterns2358 / 3251
- Counting Patterns2240 / 2721
- Pattern Positions1892 / 2266
- Distinct Substrings2116 / 2499
- Distinct Subsequences1368 / 1445
- Repeating Substring2285 / 2614
- String Functions2002 / 2095
- Inverse Suffix Array389 / 443
- String Transform692 / 817
- Substring Order I1442 / 1590
- Substring Order II982 / 1251
- Substring Distribution1346 / 1454
Geometry
- Point Location Test8636 / 9572
- Line Segment Intersection5118 / 6349
- Polygon Area5866 / 6184
- Point in Polygon3294 / 4130
- Polygon Lattice Points2674 / 2857
- Minimum Euclidean Distance2372 / 3303
- Convex Hull3927 / 4646
- Maximum Manhattan Distances864 / 897
- All Manhattan Distances900 / 987
- Intersection Points2352 / 2531
- Line Segments Trace I474 / 489
- Line Segments Trace II395 / 414
- Lines and Queries I520 / 545
- Lines and Queries II464 / 485
- Area of Rectangles1381 / 1534
- Robot Path378 / 689
Advanced Techniques
- Meet in the Middle8372 / 11221
- Hamming Distance3687 / 4025
- Corner Subgrid Check334 / 709
- Corner Subgrid Count2508 / 2850
- Reachable Nodes2616 / 2800
- Reachability Queries1759 / 2057
- Cut and Paste1809 / 1996
- Substring Reversals1600 / 1725
- Reversals and Sums1624 / 1733
- Necessary Roads2339 / 2398
- Necessary Cities2173 / 2267
- Eulerian Subgraphs926 / 975
- Monster Game I1395 / 1544
- Monster Game II1227 / 1309
- Subarray Squares1739 / 2012
- Houses and Schools949 / 1120
- Knuth Division1132 / 1267
- Apples and Bananas1330 / 1436
- One Bit Positions1003 / 1090
- Signal Processing993 / 1062
- New Roads Queries2637 / 3158
- Dynamic Connectivity1211 / 1353
- Parcel Delivery955 / 1041
- Task Assignment1100 / 1186
- Distinct Routes II729 / 820
Sliding Window Problems
- Sliding Window Sum8109 / 8371
- Sliding Window Minimum6098 / 6935
- Sliding Window Xor5954 / 6030
- Sliding Window Or2678 / 4427
- Sliding Window Distinct Values4260 / 4955
- Sliding Window Mode3313 / 3507
- Sliding Window Mex3123 / 3284
- Sliding Window Median15321 / 17402
- Sliding Window Cost10006 / 11491
- Sliding Window Inversions1676 / 1772
- Sliding Window Advertisement322 / 505
Interactive Problems
- Hidden Integer2916 / 3038
- Hidden Permutation1309 / 1513
- K-th Highest Score595 / 718
- Permuted Binary Strings701 / 720
- Colored Chairs659 / 698
- Inversion Sorting383 / 431
Bitwise Operations
- Counting Bits6272 / 8044
- Maximum Xor Subarray3704 / 4231
- Maximum Xor Subset1406 / 1543
- Number of Subset Xors1221 / 1248
- K Subset Xors637 / 746
- All Subarray Xors384 / 593
- Xor Pyramid Peak2467 / 2949
- Xor Pyramid Diagonal438 / 490
- Xor Pyramid Row377 / 441
- SOS Bit Problem2598 / 2751
- And Subset Count623 / 647
Construction Problems
- Inverse Inversions2082 / 2222
- Monotone Subsequences1257 / 1485
- Third Permutation559 / 687
- Permutation Prime Sums562 / 603
- Chess Tournament1394 / 1607
- Distinct Sums Grid200 / 299
- Filling Trominos309 / 532
- Grid Path Construction171 / 501
Advanced Graph Problems
- Nearest Shops970 / 1242
- Prüfer Code1733 / 1855
- Tree Traversals1426 / 1559
- Course Schedule II2368 / 3311
- Acyclic Graph Edges2465 / 2613
- Strongly Connected Edges1806 / 2095
- Even Outdegree Edges1586 / 1842
- Graph Girth4001 / 4507
- Fixed Length Walk Queries484 / 535
- Transfer Speeds Sum543 / 561
- MST Edge Check891 / 961
- MST Edge Set Check332 / 374
- MST Edge Cost526 / 547
- Network Breakdown1349 / 1464
- Tree Coin Collecting I460 / 499
- Tree Coin Collecting II262 / 299
- Tree Isomorphism I1234 / 1457
- Tree Isomorphism II1023 / 1169
- Flight Route Requests582 / 721
- Critical Cities507 / 756
- Visiting Cities771 / 1006
- Graph Coloring297 / 346
- Bus Companies346 / 356
- Split into Two Paths141 / 239
- Network Renovation1041 / 1366
- Forbidden Cities987 / 1272
- Creating Offices477 / 619
- New Flight Routes411 / 1042
Counting Problems
- Filled Subgrid Count I794 / 885
- Filled Subgrid Count II424 / 525
- All Letter Subgrid Count I241 / 345
- All Letter Subgrid Count II153 / 230
- Border Subgrid Count I129 / 219
- Border Subgrid Count II144 / 166
- Raab Game II145 / 165
- Empty String1928 / 2337
- Permutation Inversions1142 / 1257
- Counting Bishops448 / 501
- Counting Sequences768 / 823
- Grid Paths II854 / 1074
- Counting Permutations989 / 1114
- Grid Completion263 / 332
- Counting Reorders300 / 415
- Tournament Graph Distribution147 / 157
- Collecting Numbers Distribution155 / 162
- Functional Graph Distribution281 / 344
Additional Problems I
- Shortest Subsequence3280 / 4281
- Distinct Values Sum874 / 898
- Distinct Values Splits618 / 661
- Swap Game2266 / 2892
- Beautiful Permutation II768 / 1175
- Multiplication Table7846 / 8698
- Bubble Sort Rounds I556 / 630
- Bubble Sort Rounds II387 / 431
- Nearest Campsites I242 / 283
- Nearest Campsites II234 / 252
- Advertisement4927 / 5208
- Special Substrings1089 / 1192
- Counting LCM Arrays376 / 408
- Square Subsets288 / 317
- Subarray Sum Constraints590 / 629
- Water Containers Moves233 / 247
- Water Containers Queries268 / 283
- Stack Weights653 / 780
- Maximum Average Subarrays228 / 251
- Subsets with Fixed Average272 / 295
- Two Array Average277 / 308
- Pyramid Array869 / 1046
- Permutation Subsequence319 / 330
- Bit Inversions2585 / 2904
- Writing Numbers815 / 882
- Letter Pair Move Game236 / 326
- Maximum Building I2283 / 2383
- Sorting Methods849 / 906
- Cyclic Array1383 / 1558
- List of Sums545 / 704
Additional Problems II
- Bouncing Ball Steps318 / 351
- Bouncing Ball Cycle134 / 181
- Knight Moves Queries166 / 199
- K Subset Sums I261 / 325
- K Subset Sums II155 / 194
- Increasing Array II916 / 1045
- Food Division580 / 690
- Swap Round Sorting451 / 558
- Binary Subsequences321 / 462
- School Excursion1538 / 1625
- Coin Grid1030 / 1195
- Grid Coloring II173 / 222
- Programmers and Artists565 / 782
- Removing Digits II245 / 519
- Coin Arrangement374 / 495
- Replace with Difference177 / 210
- Grid Puzzle I608 / 666
- Grid Puzzle II592 / 647
- Bit Substrings450 / 542
- Reversal Sorting396 / 476
- Book Shop II1435 / 1634
- GCD Subsets516 / 532
- Minimum Cost Pairs182 / 228
- Same Sum Subsets158 / 301
- Mex Grid Queries931 / 1086
- Maximum Building II492 / 604
- Stick Divisions4165 / 4853
- Stick Difference105 / 337
- Coding Company1668 / 2176
- Two Stacks Sorting210 / 643