General
Introductory Problems
- Weird Algorithm161516 / 168955
- Missing Number139383 / 145972
- Repetitions121326 / 126090
- Increasing Array114116 / 118081
- Permutations100320 / 103308
- Number Spiral70959 / 77199
- Two Knights54409 / 56091
- Two Sets59167 / 63543
- Bit Strings67638 / 71317
- Trailing Zeros62832 / 66755
- Coin Piles55691 / 60819
- Palindrome Reorder51818 / 54648
- Gray Code34889 / 39104
- Tower of Hanoi32429 / 33716
- Creating Strings43690 / 44798
- Apple Division43969 / 49572
- Chessboard and Queens26575 / 27050
- Raab Game I5464 / 6202
- Mex Grid Construction5300 / 5605
- Knight Moves Grid5314 / 5431
- Grid Coloring I4449 / 4607
- Digit Queries18709 / 21654
- String Reorder4060 / 4697
- Grid Path Description10403 / 13476
Sorting and Searching
- Distinct Numbers79847 / 86195
- Apartments59584 / 65930
- Ferris Wheel57191 / 61533
- Concert Tickets45850 / 53217
- Restaurant Customers46665 / 50276
- Movie Festival45102 / 47705
- Sum of Two Values52436 / 58539
- Maximum Subarray Sum50505 / 52701
- Stick Lengths45078 / 47104
- Missing Coin Sum34141 / 35368
- Collecting Numbers35016 / 37406
- Collecting Numbers II14817 / 18808
- Playlist34933 / 39803
- Towers35052 / 37514
- Traffic Lights27222 / 30396
- Distinct Values Subarrays7314 / 8503
- Distinct Values Subsequences5605 / 6190
- Josephus Problem I20873 / 22946
- Josephus Problem II11353 / 15614
- Nested Ranges Check12194 / 13954
- Nested Ranges Count8209 / 9666
- Room Allocation20487 / 23451
- Factory Machines29478 / 32024
- Tasks and Deadlines23600 / 24098
- Reading Books19087 / 20444
- Sum of Three Values27872 / 30796
- Sum of Four Values17339 / 19259
- Nearest Smaller Values23273 / 24067
- Subarray Sums I30885 / 32886
- Subarray Sums II28067 / 33208
- Subarray Divisibility25427 / 27663
- Distinct Values Subarrays II15390 / 16861
- Array Division24132 / 25384
- Movie Festival II12921 / 15545
- Maximum Subarray Sum II12023 / 14307
Dynamic Programming
- Dice Combinations83026 / 87749
- Minimizing Coins71811 / 77049
- Coin Combinations I65644 / 70921
- Coin Combinations II55543 / 62690
- Removing Digits61777 / 63008
- Grid Paths I58069 / 59682
- Book Shop52020 / 57088
- Array Description38325 / 42481
- Counting Towers23428 / 24817
- Edit Distance38440 / 40548
- Longest Common Subsequence10618 / 11013
- Rectangle Cutting31715 / 34591
- Minimal Grid Path4654 / 8272
- Money Sums37509 / 38904
- Removal Game22580 / 29966
- Two Sets II29480 / 31681
- Mountain Range3221 / 5850
- Increasing Subsequence30155 / 33827
- Projects20875 / 23292
- Elevator Rides13379 / 16763
- Counting Tilings7845 / 8536
- Counting Numbers11135 / 12498
- Increasing Subsequence II4843 / 5636
Graph Algorithms
- Counting Rooms57377 / 60227
- Labyrinth39937 / 47601
- Building Roads49948 / 51739
- Message Route43074 / 44764
- Building Teams40665 / 42827
- Round Trip32170 / 34991
- Monsters22256 / 26106
- Shortest Routes I35390 / 38930
- Shortest Routes II28641 / 32042
- High Score17614 / 24569
- Flight Discount22752 / 26520
- Cycle Finding16099 / 19634
- Flight Routes15628 / 17421
- Round Trip II17704 / 19833
- Course Schedule23444 / 24722
- Longest Flight Route16675 / 20508
- Game Routes18544 / 19810
- Investigation13759 / 14766
- Planets Queries I11979 / 14010
- Planets Queries II4345 / 5481
- Planets Cycles7314 / 8145
- Road Reparation18181 / 18950
- Road Construction19959 / 20600
- Flight Routes Check15859 / 17163
- Planets and Kingdoms12718 / 13230
- Giant Pizza5331 / 5853
- Coin Collector8346 / 9214
- Mail Delivery6888 / 7525
- De Bruijn Sequence3639 / 3806
- Teleporters Path5270 / 6001
- Hamiltonian Flights7973 / 9075
- Knight's Tour3000 / 3623
- Download Speed5277 / 7024
- Police Chase4218 / 4720
- School Dance4630 / 4891
- Distinct Routes3263 / 4254
Range Queries
- Static Range Sum Queries40070 / 41841
- Static Range Minimum Queries27847 / 29811
- Dynamic Range Sum Queries28905 / 30180
- Dynamic Range Minimum Queries26163 / 26791
- Range Xor Queries26917 / 27272
- Range Update Queries21478 / 23003
- Forest Queries22042 / 22836
- Hotel Queries15608 / 16532
- List Removals12937 / 13586
- Salary Queries9771 / 12273
- Prefix Sum Queries8306 / 8973
- Pizzeria Queries6690 / 6930
- Visible Buildings Queries1709 / 1867
- Range Interval Queries1332 / 1786
- Subarray Sum Queries7841 / 8489
- Subarray Sum Queries II1903 / 1969
- Distinct Values Queries7363 / 9027
- Distinct Values Queries II1112 / 1266
- Increasing Array Queries2825 / 3231
- Movie Festival Queries1481 / 1645
- Forest Queries II4672 / 5017
- Range Updates and Sums6379 / 7546
- Polynomial Queries4723 / 5549
- Range Queries and Copies3350 / 3577
- Missing Coin Sum Queries766 / 1001
Tree Algorithms
- Subordinates32810 / 35106
- Tree Matching18670 / 21649
- Tree Diameter26722 / 28309
- Tree Distances I20521 / 22040
- Tree Distances II16740 / 17472
- Company Queries I18695 / 19674
- Company Queries II17510 / 18432
- Distance Queries15823 / 16979
- Counting Paths9958 / 10541
- Subtree Queries11933 / 12711
- Path Queries9586 / 10148
- Path Queries II3974 / 5926
- Distinct Colors9224 / 10152
- Finding a Centroid7446 / 7748
- Fixed-Length Paths I3646 / 4656
- Fixed-Length Paths II1729 / 3111
Mathematics
- Josephus Queries5157 / 6492
- Exponentiation26012 / 27747
- Exponentiation II18216 / 21738
- Counting Divisors23714 / 26747
- Common Divisors15327 / 17735
- Sum of Divisors8603 / 12791
- Divisor Analysis5905 / 7883
- Prime Multiples6847 / 7972
- Counting Coprime Pairs4531 / 5248
- Next Prime2065 / 2370
- Binomial Coefficients11029 / 12213
- Creating Strings II9227 / 9731
- Distributing Apples8799 / 9456
- Christmas Party7228 / 7736
- Permutation Order992 / 1014
- Permutation Rounds1353 / 1509
- Bracket Sequences I4896 / 5328
- Bracket Sequences II2591 / 2957
- Counting Necklaces2366 / 2560
- Counting Grids1970 / 2094
- Fibonacci Numbers7399 / 9260
- Throwing Dice3861 / 4197
- Graph Paths I3725 / 3985
- Graph Paths II3114 / 3260
- System of Linear Equations499 / 545
- Sum of Four Squares727 / 854
- Triangle Number Sums620 / 753
- Dice Probability3312 / 3568
- Moving Robots1717 / 1814
- Candy Lottery1640 / 3248
- Inversion Probability454 / 2413
- Stick Game3762 / 3852
- Nim Game I5003 / 5186
- Nim Game II3956 / 4113
- Stair Game2697 / 2928
- Grundy's Game1879 / 2459
- Another Game2113 / 2276
String Algorithms
- Word Combinations6345 / 9117
- String Matching12254 / 16334
- Finding Borders8990 / 9821
- Finding Periods6371 / 7212
- Minimal Rotation3097 / 4674
- Longest Palindrome4663 / 6146
- All Palindromes670 / 762
- Required Substring1787 / 2700
- Palindrome Queries2191 / 2555
- Finding Patterns2052 / 2896
- Counting Patterns1942 / 2400
- Pattern Positions1635 / 1987
- Distinct Substrings1849 / 2202
- Distinct Subsequences1158 / 1232
- Repeating Substring1995 / 2313
- String Functions1741 / 1825
- Inverse Suffix Array249 / 294
- String Transform568 / 686
- Substring Order I1257 / 1401
- Substring Order II830 / 1079
- Substring Distribution1168 / 1267
Geometry
- Point Location Test7871 / 8767
- Line Segment Intersection4666 / 5843
- Polygon Area5383 / 5689
- Point in Polygon2962 / 3766
- Polygon Lattice Points2500 / 2583
- Minimum Euclidean Distance2145 / 3042
- Convex Hull3620 / 4315
- Maximum Manhattan Distances639 / 661
- All Manhattan Distances627 / 685
- Intersection Points2113 / 2277
- Line Segments Trace I341 / 353
- Line Segments Trace II281 / 297
- Lines and Queries I390 / 408
- Lines and Queries II338 / 349
- Area of Rectangles1221 / 1363
- Robot Path327 / 606
Advanced Techniques
- Meet in the Middle7136 / 9827
- Hamming Distance3393 / 3709
- Corner Subgrid Check352 / 538
- Corner Subgrid Count2342 / 2629
- Reachable Nodes2408 / 2589
- Reachability Queries1604 / 1886
- Cut and Paste1639 / 1816
- Substring Reversals1425 / 1545
- Reversals and Sums1446 / 1550
- Necessary Roads2094 / 2151
- Necessary Cities1935 / 2025
- Eulerian Subgraphs848 / 892
- Monster Game I1230 / 1366
- Monster Game II1090 / 1166
- Subarray Squares1533 / 1797
- Houses and Schools820 / 981
- Knuth Division1005 / 1133
- Apples and Bananas1149 / 1245
- One Bit Positions898 / 979
- Signal Processing860 / 920
- New Roads Queries2341 / 2828
- Dynamic Connectivity1067 / 1202
- Parcel Delivery821 / 906
- Task Assignment953 / 1028
- Distinct Routes II620 / 706
Sliding Window Problems
- Sliding Window Sum5809 / 6025
- Sliding Window Minimum4333 / 4952
- Sliding Window Xor4235 / 4293
- Sliding Window Or1870 / 3206
- Sliding Window Distinct Values2886 / 3542
- Sliding Window Mode2352 / 2496
- Sliding Window Mex2167 / 2287
- Sliding Window Median14228 / 16236
- Sliding Window Cost9326 / 10754
- Sliding Window Inversions1218 / 1294
- Sliding Window Advertisement231 / 366
Interactive Problems
- Hidden Integer2306 / 2398
- Hidden Permutation978 / 1145
- K-th Highest Score430 / 520
- Permuted Binary Strings530 / 544
- Colored Chairs481 / 507
- Inversion Sorting277 / 309
Bitwise Operations
- Counting Bits5270 / 6813
- Maximum Xor Subarray3143 / 3579
- Maximum Xor Subset1020 / 1112
- Number of Subset Xors907 / 926
- K Subset Xors454 / 541
- All Subarray Xors280 / 459
- Xor Pyramid Peak2132 / 2579
- Xor Pyramid Diagonal324 / 362
- Xor Pyramid Row273 / 322
- SOS Bit Problem2242 / 2384
- And Subset Count437 / 454
Construction Problems
- Inverse Inversions1745 / 1855
- Monotone Subsequences1048 / 1237
- Third Permutation415 / 505
- Permutation Prime Sums419 / 453
- Chess Tournament1246 / 1442
- Distinct Sums Grid132 / 205
- Filling Trominos244 / 439
- Grid Path Construction121 / 438
Advanced Graph Problems
- Nearest Shops714 / 923
- Prüfer Code1583 / 1700
- Tree Traversals1283 / 1414
- Course Schedule II1989 / 2844
- Acyclic Graph Edges2278 / 2414
- Strongly Connected Edges1553 / 1834
- Even Outdegree Edges1409 / 1644
- Graph Girth3543 / 4028
- Fixed Length Walk Queries359 / 397
- Transfer Speeds Sum420 / 433
- MST Edge Check634 / 691
- MST Edge Set Check238 / 270
- MST Edge Cost389 / 407
- Network Breakdown1191 / 1299
- Tree Coin Collecting I340 / 372
- Tree Coin Collecting II182 / 212
- Tree Isomorphism I1128 / 1345
- Tree Isomorphism II927 / 1071
- Flight Route Requests512 / 632
- Critical Cities436 / 673
- Visiting Cities699 / 923
- Graph Coloring228 / 268
- Bus Companies265 / 272
- Split into Two Paths95 / 172
- Network Renovation960 / 1275
- Forbidden Cities869 / 1134
- Creating Offices424 / 554
- New Flight Routes337 / 909
Counting Problems
- Filled Subgrid Count I583 / 656
- Filled Subgrid Count II309 / 382
- All Letter Subgrid Count I167 / 257
- All Letter Subgrid Count II133 / 171
- Border Subgrid Count I89 / 156
- Border Subgrid Count II99 / 116
- Raab Game II105 / 120
- Empty String1716 / 2087
- Permutation Inversions1056 / 1165
- Counting Bishops402 / 448
- Counting Sequences669 / 723
- Grid Paths II777 / 972
- Counting Permutations912 / 1029
- Grid Completion229 / 290
- Counting Reorders247 / 356
- Tournament Graph Distribution105 / 112
- Collecting Numbers Distribution111 / 119
- Functional Graph Distribution249 / 307
Additional Problems I
- Shortest Subsequence3062 / 4035
- Distinct Values Sum660 / 683
- Distinct Values Splits477 / 506
- Swap Game2073 / 2672
- Beautiful Permutation II529 / 810
- Multiplication Table7030 / 7825
- Bubble Sort Rounds I398 / 456
- Bubble Sort Rounds II260 / 295
- Nearest Campsites I176 / 205
- Nearest Campsites II172 / 184
- Advertisement4507 / 4777
- Special Substrings998 / 1095
- Counting LCM Arrays272 / 298
- Square Subsets221 / 246
- Subarray Sum Constraints389 / 415
- Water Containers Moves170 / 180
- Water Containers Queries207 / 217
- Stack Weights598 / 713
- Maximum Average Subarrays164 / 181
- Subsets with Fixed Average206 / 223
- Two Array Average203 / 227
- Pyramid Array770 / 933
- Permutation Subsequence246 / 254
- Bit Inversions2372 / 2684
- Writing Numbers749 / 809
- Letter Pair Move Game205 / 283
- Maximum Building I2126 / 2217
- Sorting Methods786 / 840
- Cyclic Array1229 / 1399
- List of Sums499 / 649
Additional Problems II
- Bouncing Ball Steps229 / 251
- Bouncing Ball Cycle89 / 127
- Knight Moves Queries114 / 137
- K Subset Sums I183 / 239
- K Subset Sums II102 / 134
- Increasing Array II813 / 929
- Food Division526 / 634
- Swap Round Sorting420 / 517
- Binary Subsequences295 / 430
- School Excursion1408 / 1492
- Coin Grid901 / 1052
- Grid Coloring II135 / 176
- Programmers and Artists511 / 714
- Removing Digits II216 / 473
- Coin Arrangement339 / 452
- Replace with Difference128 / 153
- Grid Puzzle I545 / 600
- Grid Puzzle II521 / 575
- Bit Substrings404 / 490
- Reversal Sorting360 / 435
- Book Shop II1262 / 1438
- GCD Subsets407 / 419
- Minimum Cost Pairs138 / 181
- Same Sum Subsets111 / 213
- Mex Grid Queries865 / 1013
- Maximum Building II453 / 558
- Stick Divisions3890 / 4556
- Stick Difference57 / 249
- Coding Company1531 / 2005
- Two Stacks Sorting180 / 582