General
Introductory Problems
- Weird Algorithm172195 / 179959
- Missing Number148708 / 155491
- Repetitions129298 / 134212
- Increasing Array121847 / 125937
- Permutations106854 / 109953
- Number Spiral75800 / 82253
- Two Knights58443 / 60185
- Two Sets63501 / 68007
- Bit Strings72345 / 76190
- Trailing Zeros67051 / 71162
- Coin Piles59611 / 64904
- Palindrome Reorder55409 / 58334
- Gray Code37768 / 42142
- Tower of Hanoi35180 / 36528
- Creating Strings46724 / 47865
- Apple Division47377 / 53161
- Chessboard and Queens28837 / 29322
- Raab Game I7111 / 8013
- Mex Grid Construction6925 / 7265
- Knight Moves Grid7003 / 7159
- Grid Coloring I5889 / 6099
- Digit Queries20261 / 23271
- String Reorder5282 / 6047
- Grid Path Description11332 / 14545
Sorting and Searching
- Distinct Numbers85479 / 92042
- Apartments64148 / 70641
- Ferris Wheel61720 / 66172
- Concert Tickets49542 / 57208
- Restaurant Customers50389 / 54141
- Movie Festival48953 / 51653
- Sum of Two Values56742 / 63098
- Maximum Subarray Sum54237 / 56492
- Stick Lengths48590 / 50681
- Missing Coin Sum37095 / 38376
- Collecting Numbers37966 / 40462
- Collecting Numbers II16590 / 20728
- Playlist37944 / 43019
- Towers37966 / 40514
- Traffic Lights29522 / 32849
- Distinct Values Subarrays9627 / 10839
- Distinct Values Subsequences7399 / 8074
- Josephus Problem I22896 / 25045
- Josephus Problem II12514 / 17119
- Nested Ranges Check13623 / 15444
- Nested Ranges Count9127 / 10681
- Room Allocation22323 / 25434
- Factory Machines32290 / 34921
- Tasks and Deadlines25848 / 26359
- Reading Books20947 / 22364
- Sum of Three Values30312 / 33346
- Sum of Four Values18914 / 20888
- Nearest Smaller Values25328 / 26151
- Subarray Sums I33572 / 35636
- Subarray Sums II30615 / 35932
- Subarray Divisibility27735 / 30031
- Distinct Values Subarrays II16929 / 18431
- Array Division26240 / 27517
- Movie Festival II14226 / 16986
- Maximum Subarray Sum II13256 / 15643
Dynamic Programming
- Dice Combinations89554 / 94520
- Minimizing Coins77504 / 82968
- Coin Combinations I70894 / 76427
- Coin Combinations II60091 / 67547
- Removing Digits66710 / 68009
- Grid Paths I62717 / 64398
- Book Shop56523 / 61805
- Array Description41809 / 46132
- Counting Towers25888 / 27358
- Edit Distance41711 / 43894
- Longest Common Subsequence13745 / 14213
- Rectangle Cutting34416 / 37424
- Minimal Grid Path6302 / 10620
- Money Sums40629 / 42082
- Removal Game24915 / 32395
- Two Sets II31990 / 34263
- Mountain Range4348 / 7513
- Increasing Subsequence32565 / 36403
- Projects22785 / 25293
- Elevator Rides14822 / 18409
- Counting Tilings8707 / 9425
- Counting Numbers12934 / 14353
- Increasing Subsequence II5738 / 6712
Graph Algorithms
- Counting Rooms62132 / 65066
- Labyrinth43943 / 51826
- Building Roads54406 / 56252
- Message Route47099 / 48838
- Building Teams44488 / 46697
- Round Trip35235 / 38149
- Monsters24832 / 28789
- Shortest Routes I38875 / 42486
- Shortest Routes II31444 / 34994
- High Score20002 / 27193
- Flight Discount25588 / 29520
- Cycle Finding18047 / 21699
- Flight Routes17623 / 19497
- Round Trip II19609 / 21826
- Course Schedule25992 / 27303
- Longest Flight Route18916 / 22896
- Game Routes20678 / 21979
- Investigation15563 / 16627
- Planets Queries I13516 / 15647
- Planets Queries II4919 / 6135
- Planets Cycles8211 / 9091
- Road Reparation20211 / 21009
- Road Construction22068 / 22744
- Flight Routes Check17535 / 18884
- Planets and Kingdoms14252 / 14858
- Giant Pizza6021 / 6573
- Coin Collector9430 / 10332
- Mail Delivery7562 / 8226
- De Bruijn Sequence4010 / 4190
- Teleporters Path5848 / 6599
- Hamiltonian Flights8906 / 10078
- Knight's Tour3362 / 4032
- Download Speed5841 / 7637
- Police Chase4635 / 5157
- School Dance5097 / 5375
- Distinct Routes3618 / 4656
Range Queries
- Static Range Sum Queries43380 / 45286
- Static Range Minimum Queries29862 / 31933
- Dynamic Range Sum Queries31071 / 32402
- Dynamic Range Minimum Queries28100 / 28761
- Range Xor Queries28826 / 29207
- Range Update Queries23165 / 24757
- Forest Queries23869 / 24696
- Hotel Queries16867 / 17818
- List Removals14001 / 14677
- Salary Queries10765 / 13355
- Prefix Sum Queries9050 / 9730
- Pizzeria Queries7268 / 7520
- Visible Buildings Queries2129 / 2313
- Range Interval Queries1620 / 2167
- Subarray Sum Queries8400 / 9070
- Subarray Sum Queries II2378 / 2453
- Distinct Values Queries7951 / 9655
- Distinct Values Queries II1344 / 1528
- Increasing Array Queries3044 / 3469
- Movie Festival Queries1679 / 1849
- Forest Queries II4986 / 5338
- Range Updates and Sums6931 / 8126
- Polynomial Queries5114 / 5980
- Range Queries and Copies3622 / 3860
- Missing Coin Sum Queries833 / 1150
Tree Algorithms
- Subordinates35734 / 38156
- Tree Matching20564 / 23715
- Tree Diameter29198 / 30847
- Tree Distances I22568 / 24155
- Tree Distances II18394 / 19209
- Company Queries I20655 / 21680
- Company Queries II19302 / 20276
- Distance Queries17428 / 18626
- Counting Paths10994 / 11606
- Subtree Queries12984 / 13791
- Path Queries10457 / 11031
- Path Queries II4400 / 6460
- Distinct Colors10065 / 11015
- Finding a Centroid8186 / 8509
- Fixed-Length Paths I4081 / 5139
- Fixed-Length Paths II1973 / 3455
Mathematics
- Josephus Queries5657 / 7069
- Exponentiation27852 / 29638
- Exponentiation II19450 / 23100
- Counting Divisors25523 / 28732
- Common Divisors16422 / 18949
- Sum of Divisors9328 / 13699
- Divisor Analysis6411 / 8498
- Prime Multiples7441 / 8612
- Counting Coprime Pairs4949 / 5705
- Next Prime2524 / 2877
- Binomial Coefficients11929 / 13171
- Creating Strings II9880 / 10400
- Distributing Apples9413 / 10094
- Christmas Party7839 / 8362
- Permutation Order1209 / 1244
- Permutation Rounds1736 / 1923
- Bracket Sequences I5240 / 5686
- Bracket Sequences II2769 / 3153
- Counting Necklaces2540 / 2743
- Counting Grids2126 / 2257
- Fibonacci Numbers7855 / 9775
- Throwing Dice4137 / 4481
- Graph Paths I4013 / 4277
- Graph Paths II3354 / 3510
- System of Linear Equations607 / 661
- Sum of Four Squares901 / 1045
- Triangle Number Sums760 / 914
- Dice Probability3512 / 3771
- Moving Robots1823 / 1922
- Candy Lottery1844 / 3478
- Inversion Probability547 / 2593
- Stick Game4036 / 4132
- Nim Game I5369 / 5564
- Nim Game II4251 / 4416
- Stair Game2883 / 3126
- Grundy's Game2008 / 2632
- Another Game2278 / 2450
String Algorithms
- Word Combinations6921 / 9812
- String Matching13261 / 17526
- Finding Borders9746 / 10608
- Finding Periods6962 / 7844
- Minimal Rotation3452 / 5074
- Longest Palindrome5108 / 6641
- All Palindromes882 / 987
- Required Substring1963 / 2917
- Palindrome Queries2405 / 2778
- Finding Patterns2266 / 3136
- Counting Patterns2148 / 2625
- Pattern Positions1811 / 2179
- Distinct Substrings2033 / 2406
- Distinct Subsequences1299 / 1376
- Repeating Substring2205 / 2529
- String Functions1936 / 2029
- Inverse Suffix Array352 / 403
- String Transform661 / 787
- Substring Order I1393 / 1541
- Substring Order II938 / 1206
- Substring Distribution1294 / 1400
Geometry
- Point Location Test8367 / 9289
- Line Segment Intersection4971 / 6187
- Polygon Area5711 / 6026
- Point in Polygon3186 / 4012
- Polygon Lattice Points2585 / 2768
- Minimum Euclidean Distance2291 / 3206
- Convex Hull3824 / 4537
- Maximum Manhattan Distances786 / 817
- All Manhattan Distances814 / 896
- Intersection Points2261 / 2434
- Line Segments Trace I437 / 451
- Line Segments Trace II363 / 382
- Lines and Queries I482 / 505
- Lines and Queries II428 / 448
- Area of Rectangles1315 / 1467
- Robot Path359 / 660
Advanced Techniques
- Meet in the Middle7731 / 10499
- Hamming Distance3560 / 3891
- Corner Subgrid Check277 / 650
- Corner Subgrid Count2447 / 2766
- Reachable Nodes2546 / 2732
- Reachability Queries1709 / 2005
- Cut and Paste1747 / 1932
- Substring Reversals1538 / 1665
- Reversals and Sums1562 / 1670
- Necessary Roads2247 / 2305
- Necessary Cities2090 / 2183
- Eulerian Subgraphs895 / 944
- Monster Game I1340 / 1486
- Monster Game II1181 / 1262
- Subarray Squares1677 / 1948
- Houses and Schools910 / 1076
- Knuth Division1087 / 1221
- Apples and Bananas1249 / 1353
- One Bit Positions957 / 1041
- Signal Processing931 / 995
- New Roads Queries2532 / 3047
- Dynamic Connectivity1162 / 1304
- Parcel Delivery903 / 990
- Task Assignment1044 / 1131
- Distinct Routes II688 / 779
Sliding Window Problems
- Sliding Window Sum7385 / 7630
- Sliding Window Minimum5522 / 6289
- Sliding Window Xor5437 / 5513
- Sliding Window Or2442 / 4068
- Sliding Window Distinct Values3821 / 4512
- Sliding Window Mode3007 / 3185
- Sliding Window Mex2840 / 2989
- Sliding Window Median14968 / 17023
- Sliding Window Cost9782 / 11245
- Sliding Window Inversions1539 / 1631
- Sliding Window Advertisement302 / 477
Interactive Problems
- Hidden Integer2728 / 2846
- Hidden Permutation1212 / 1404
- K-th Highest Score547 / 659
- Permuted Binary Strings649 / 667
- Colored Chairs608 / 645
- Inversion Sorting352 / 395
Bitwise Operations
- Counting Bits5939 / 7630
- Maximum Xor Subarray3530 / 4029
- Maximum Xor Subset1262 / 1382
- Number of Subset Xors1109 / 1131
- K Subset Xors571 / 672
- All Subarray Xors342 / 540
- Xor Pyramid Peak2338 / 2814
- Xor Pyramid Diagonal387 / 436
- Xor Pyramid Row336 / 392
- SOS Bit Problem2465 / 2611
- And Subset Count551 / 574
Construction Problems
- Inverse Inversions1968 / 2100
- Monotone Subsequences1193 / 1410
- Third Permutation510 / 630
- Permutation Prime Sums517 / 556
- Chess Tournament1347 / 1554
- Distinct Sums Grid182 / 268
- Filling Trominos295 / 506
- Grid Path Construction159 / 482
Advanced Graph Problems
- Nearest Shops870 / 1116
- Prüfer Code1677 / 1800
- Tree Traversals1376 / 1509
- Course Schedule II2247 / 3160
- Acyclic Graph Edges2403 / 2544
- Strongly Connected Edges1721 / 2007
- Even Outdegree Edges1520 / 1765
- Graph Girth3836 / 4332
- Fixed Length Walk Queries435 / 484
- Transfer Speeds Sum500 / 515
- MST Edge Check807 / 876
- MST Edge Set Check300 / 338
- MST Edge Cost482 / 504
- Network Breakdown1305 / 1420
- Tree Coin Collecting I427 / 461
- Tree Coin Collecting II243 / 278
- Tree Isomorphism I1199 / 1415
- Tree Isomorphism II990 / 1135
- Flight Route Requests562 / 693
- Critical Cities483 / 726
- Visiting Cities745 / 977
- Graph Coloring273 / 319
- Bus Companies319 / 329
- Split into Two Paths128 / 219
- Network Renovation1017 / 1338
- Forbidden Cities939 / 1220
- Creating Offices459 / 599
- New Flight Routes387 / 1002
Counting Problems
- Filled Subgrid Count I718 / 805
- Filled Subgrid Count II393 / 482
- All Letter Subgrid Count I222 / 322
- All Letter Subgrid Count II164 / 213
- Border Subgrid Count I118 / 202
- Border Subgrid Count II128 / 149
- Raab Game II133 / 152
- Empty String1863 / 2256
- Permutation Inversions1108 / 1223
- Counting Bishops434 / 483
- Counting Sequences742 / 798
- Grid Paths II832 / 1044
- Counting Permutations963 / 1087
- Grid Completion247 / 313
- Counting Reorders286 / 399
- Tournament Graph Distribution133 / 142
- Collecting Numbers Distribution139 / 146
- Functional Graph Distribution268 / 329
Additional Problems I
- Shortest Subsequence3206 / 4199
- Distinct Values Sum805 / 829
- Distinct Values Splits568 / 608
- Swap Game2216 / 2836
- Beautiful Permutation II696 / 1076
- Multiplication Table7560 / 8403
- Bubble Sort Rounds I513 / 582
- Bubble Sort Rounds II350 / 390
- Nearest Campsites I221 / 258
- Nearest Campsites II216 / 231
- Advertisement4807 / 5086
- Special Substrings1058 / 1161
- Counting LCM Arrays339 / 370
- Square Subsets260 / 286
- Subarray Sum Constraints523 / 557
- Water Containers Moves210 / 223
- Water Containers Queries244 / 257
- Stack Weights632 / 757
- Maximum Average Subarrays204 / 224
- Subsets with Fixed Average244 / 267
- Two Array Average250 / 279
- Pyramid Array831 / 1002
- Permutation Subsequence293 / 304
- Bit Inversions2510 / 2827
- Writing Numbers793 / 857
- Letter Pair Move Game223 / 310
- Maximum Building I2234 / 2333
- Sorting Methods825 / 881
- Cyclic Array1332 / 1506
- List of Sums528 / 685
Additional Problems II
- Bouncing Ball Steps287 / 318
- Bouncing Ball Cycle118 / 164
- Knight Moves Queries148 / 177
- K Subset Sums I231 / 295
- K Subset Sums II142 / 178
- Increasing Array II882 / 1006
- Food Division560 / 670
- Swap Round Sorting440 / 545
- Binary Subsequences311 / 450
- School Excursion1502 / 1587
- Coin Grid979 / 1143
- Grid Coloring II161 / 209
- Programmers and Artists550 / 766
- Removing Digits II237 / 506
- Coin Arrangement365 / 483
- Replace with Difference156 / 186
- Grid Puzzle I589 / 646
- Grid Puzzle II572 / 626
- Bit Substrings434 / 525
- Reversal Sorting384 / 463
- Book Shop II1385 / 1576
- GCD Subsets482 / 497
- Minimum Cost Pairs164 / 209
- Same Sum Subsets145 / 279
- Mex Grid Queries905 / 1059
- Maximum Building II478 / 587
- Stick Divisions4072 / 4752
- Stick Difference90 / 307
- Coding Company1622 / 2117
- Two Stacks Sorting198 / 621