General
Introductory Problems
- Weird Algorithm176555 / 184415
- Missing Number152308 / 159199
- Repetitions132375 / 137345
- Increasing Array124786 / 128920
- Permutations109341 / 112493
- Number Spiral77692 / 84228
- Two Knights59925 / 61690
- Two Sets65164 / 69714
- Bit Strings74110 / 77991
- Trailing Zeros68630 / 72779
- Coin Piles61043 / 66401
- Palindrome Reorder56739 / 59688
- Gray Code38770 / 43233
- Tower of Hanoi36157 / 37534
- Creating Strings47877 / 49034
- Apple Division48597 / 54455
- Chessboard and Queens29571 / 30069
- Raab Game I7719 / 8647
- Mex Grid Construction7491 / 7853
- Knight Moves Grid7552 / 7717
- Grid Coloring I6347 / 6570
- Digit Queries20783 / 23813
- String Reorder5684 / 6487
- Grid Path Description11645 / 14907
Sorting and Searching
- Distinct Numbers87782 / 94446
- Apartments65991 / 72556
- Ferris Wheel63588 / 68100
- Concert Tickets51000 / 58790
- Restaurant Customers51919 / 55729
- Movie Festival50472 / 53203
- Sum of Two Values58319 / 64784
- Maximum Subarray Sum55665 / 57940
- Stick Lengths49887 / 52008
- Missing Coin Sum38196 / 39489
- Collecting Numbers39123 / 41639
- Collecting Numbers II17214 / 21412
- Playlist39053 / 44210
- Towers39021 / 41621
- Traffic Lights30386 / 33753
- Distinct Values Subarrays10471 / 11717
- Distinct Values Subsequences8076 / 8781
- Josephus Problem I23672 / 25862
- Josephus Problem II12891 / 17644
- Nested Ranges Check14120 / 15953
- Nested Ranges Count9447 / 11035
- Room Allocation23040 / 26210
- Factory Machines33418 / 36067
- Tasks and Deadlines26661 / 27178
- Reading Books21633 / 23074
- Sum of Three Values31152 / 34212
- Sum of Four Values19453 / 21456
- Nearest Smaller Values26081 / 26914
- Subarray Sums I34626 / 36698
- Subarray Sums II31561 / 36970
- Subarray Divisibility28572 / 30901
- Distinct Values Subarrays II17488 / 19002
- Array Division27073 / 28375
- Movie Festival II14719 / 17523
- Maximum Subarray Sum II13732 / 16170
Dynamic Programming
- Dice Combinations92219 / 97310
- Minimizing Coins79830 / 85432
- Coin Combinations I72971 / 78583
- Coin Combinations II61890 / 69491
- Removing Digits68775 / 70130
- Grid Paths I64588 / 66282
- Book Shop58285 / 63670
- Array Description43206 / 47615
- Counting Towers26924 / 28416
- Edit Distance42999 / 45213
- Longest Common Subsequence15056 / 15551
- Rectangle Cutting35518 / 38582
- Minimal Grid Path7011 / 11604
- Money Sums41878 / 43354
- Removal Game25995 / 33504
- Two Sets II33080 / 35368
- Mountain Range4846 / 8283
- Increasing Subsequence33579 / 37493
- Projects23633 / 26185
- Elevator Rides15512 / 19182
- Counting Tilings9089 / 9824
- Counting Numbers13597 / 15033
- Increasing Subsequence II6098 / 7154
Graph Algorithms
- Counting Rooms64193 / 67176
- Labyrinth45622 / 53596
- Building Roads56215 / 58085
- Message Route48752 / 50517
- Building Teams46015 / 48237
- Round Trip36474 / 39435
- Monsters25916 / 29924
- Shortest Routes I40266 / 43900
- Shortest Routes II32550 / 36132
- High Score20905 / 28177
- Flight Discount26789 / 30754
- Cycle Finding18896 / 22567
- Flight Routes18429 / 20343
- Round Trip II20457 / 22692
- Course Schedule27013 / 28325
- Longest Flight Route19806 / 23817
- Game Routes21591 / 22913
- Investigation16375 / 17467
- Planets Queries I14202 / 16375
- Planets Queries II5156 / 6399
- Planets Cycles8571 / 9470
- Road Reparation21015 / 21829
- Road Construction22917 / 23606
- Flight Routes Check18210 / 19575
- Planets and Kingdoms14836 / 15445
- Giant Pizza6241 / 6811
- Coin Collector9852 / 10771
- Mail Delivery7854 / 8522
- De Bruijn Sequence4136 / 4321
- Teleporters Path6093 / 6849
- Hamiltonian Flights9289 / 10507
- Knight's Tour3478 / 4158
- Download Speed6050 / 7874
- Police Chase4839 / 5368
- School Dance5306 / 5590
- Distinct Routes3747 / 4797
Range Queries
- Static Range Sum Queries44891 / 46859
- Static Range Minimum Queries30858 / 33028
- Dynamic Range Sum Queries32104 / 33462
- Dynamic Range Minimum Queries28998 / 29670
- Range Xor Queries29612 / 29999
- Range Update Queries23954 / 25571
- Forest Queries24599 / 25434
- Hotel Queries17449 / 18412
- List Removals14505 / 15190
- Salary Queries11206 / 13851
- Prefix Sum Queries9395 / 10094
- Pizzeria Queries7498 / 7753
- Visible Buildings Queries2290 / 2487
- Range Interval Queries1748 / 2320
- Subarray Sum Queries8660 / 9340
- Subarray Sum Queries II2579 / 2657
- Distinct Values Queries8212 / 9937
- Distinct Values Queries II1444 / 1640
- Increasing Array Queries3120 / 3548
- Movie Festival Queries1742 / 1915
- Forest Queries II5101 / 5456
- Range Updates and Sums7183 / 8400
- Polynomial Queries5269 / 6143
- Range Queries and Copies3716 / 3957
- Missing Coin Sum Queries877 / 1199
Tree Algorithms
- Subordinates36943 / 39411
- Tree Matching21374 / 24594
- Tree Diameter30225 / 31892
- Tree Distances I23474 / 25080
- Tree Distances II19117 / 19956
- Company Queries I21504 / 22553
- Company Queries II20103 / 21093
- Distance Queries18136 / 19357
- Counting Paths11462 / 12083
- Subtree Queries13468 / 14296
- Path Queries10853 / 11438
- Path Queries II4562 / 6664
- Distinct Colors10414 / 11377
- Finding a Centroid8472 / 8799
- Fixed-Length Paths I4239 / 5310
- Fixed-Length Paths II2079 / 3596
Mathematics
- Josephus Queries5871 / 7312
- Exponentiation28582 / 30398
- Exponentiation II19964 / 23667
- Counting Divisors26280 / 29563
- Common Divisors16900 / 19468
- Sum of Divisors9629 / 14047
- Divisor Analysis6612 / 8725
- Prime Multiples7675 / 8862
- Counting Coprime Pairs5083 / 5849
- Next Prime2714 / 3084
- Binomial Coefficients12296 / 13556
- Creating Strings II10178 / 10711
- Distributing Apples9728 / 10433
- Christmas Party8079 / 8606
- Permutation Order1303 / 1338
- Permutation Rounds1892 / 2084
- Bracket Sequences I5418 / 5872
- Bracket Sequences II2889 / 3280
- Counting Necklaces2616 / 2825
- Counting Grids2202 / 2336
- Fibonacci Numbers8040 / 9994
- Throwing Dice4248 / 4594
- Graph Paths I4124 / 4392
- Graph Paths II3457 / 3617
- System of Linear Equations658 / 713
- Sum of Four Squares935 / 1118
- Triangle Number Sums818 / 978
- Dice Probability3641 / 3908
- Moving Robots1887 / 1987
- Candy Lottery1964 / 3626
- Inversion Probability588 / 2677
- Stick Game4151 / 4248
- Nim Game I5546 / 5748
- Nim Game II4390 / 4557
- Stair Game2965 / 3211
- Grundy's Game2077 / 2716
- Another Game2350 / 2524
String Algorithms
- Word Combinations7163 / 10130
- String Matching13625 / 17949
- Finding Borders10038 / 10915
- Finding Periods7181 / 8073
- Minimal Rotation3582 / 5226
- Longest Palindrome5273 / 6830
- All Palindromes964 / 1078
- Required Substring2018 / 2984
- Palindrome Queries2461 / 2837
- Finding Patterns2337 / 3228
- Counting Patterns2222 / 2703
- Pattern Positions1877 / 2249
- Distinct Substrings2096 / 2481
- Distinct Subsequences1349 / 1426
- Repeating Substring2262 / 2592
- String Functions1985 / 2078
- Inverse Suffix Array377 / 431
- String Transform685 / 810
- Substring Order I1432 / 1580
- Substring Order II975 / 1242
- Substring Distribution1335 / 1442
Geometry
- Point Location Test8585 / 9517
- Line Segment Intersection5089 / 6317
- Polygon Area5841 / 6158
- Point in Polygon3275 / 4109
- Polygon Lattice Points2660 / 2843
- Minimum Euclidean Distance2359 / 3287
- Convex Hull3907 / 4624
- Maximum Manhattan Distances848 / 881
- All Manhattan Distances887 / 972
- Intersection Points2322 / 2499
- Line Segments Trace I463 / 478
- Line Segments Trace II386 / 405
- Lines and Queries I507 / 531
- Lines and Queries II453 / 473
- Area of Rectangles1369 / 1522
- Robot Path373 / 679
Advanced Techniques
- Meet in the Middle8292 / 11121
- Hamming Distance3663 / 4002
- Corner Subgrid Check322 / 698
- Corner Subgrid Count2496 / 2838
- Reachable Nodes2602 / 2786
- Reachability Queries1743 / 2040
- Cut and Paste1796 / 1983
- Substring Reversals1587 / 1712
- Reversals and Sums1614 / 1723
- Necessary Roads2321 / 2381
- Necessary Cities2157 / 2250
- Eulerian Subgraphs921 / 970
- Monster Game I1380 / 1527
- Monster Game II1219 / 1300
- Subarray Squares1725 / 1998
- Houses and Schools938 / 1109
- Knuth Division1124 / 1259
- Apples and Bananas1311 / 1416
- One Bit Positions991 / 1078
- Signal Processing975 / 1040
- New Roads Queries2613 / 3136
- Dynamic Connectivity1195 / 1335
- Parcel Delivery948 / 1034
- Task Assignment1092 / 1178
- Distinct Routes II721 / 812
Sliding Window Problems
- Sliding Window Sum7979 / 8235
- Sliding Window Minimum6004 / 6835
- Sliding Window Xor5870 / 5946
- Sliding Window Or2641 / 4370
- Sliding Window Distinct Values4168 / 4860
- Sliding Window Mode3258 / 3448
- Sliding Window Mex3077 / 3236
- Sliding Window Median15273 / 17352
- Sliding Window Cost9971 / 11453
- Sliding Window Inversions1648 / 1743
- Sliding Window Advertisement319 / 502
Interactive Problems
- Hidden Integer2884 / 3004
- Hidden Permutation1298 / 1503
- K-th Highest Score594 / 715
- Permuted Binary Strings693 / 712
- Colored Chairs653 / 692
- Inversion Sorting379 / 427
Bitwise Operations
- Counting Bits6211 / 7971
- Maximum Xor Subarray3666 / 4189
- Maximum Xor Subset1374 / 1508
- Number of Subset Xors1197 / 1223
- K Subset Xors629 / 737
- All Subarray Xors378 / 582
- Xor Pyramid Peak2439 / 2920
- Xor Pyramid Diagonal429 / 480
- Xor Pyramid Row370 / 433
- SOS Bit Problem2578 / 2730
- And Subset Count610 / 633
Construction Problems
- Inverse Inversions2061 / 2199
- Monotone Subsequences1249 / 1475
- Third Permutation552 / 680
- Permutation Prime Sums558 / 598
- Chess Tournament1387 / 1597
- Distinct Sums Grid197 / 294
- Filling Trominos308 / 530
- Grid Path Construction170 / 497
Advanced Graph Problems
- Nearest Shops948 / 1219
- Prüfer Code1722 / 1845
- Tree Traversals1416 / 1549
- Course Schedule II2345 / 3283
- Acyclic Graph Edges2453 / 2600
- Strongly Connected Edges1788 / 2077
- Even Outdegree Edges1578 / 1830
- Graph Girth3971 / 4476
- Fixed Length Walk Queries476 / 527
- Transfer Speeds Sum535 / 552
- MST Edge Check875 / 947
- MST Edge Set Check324 / 366
- MST Edge Cost518 / 540
- Network Breakdown1341 / 1456
- Tree Coin Collecting I456 / 495
- Tree Coin Collecting II258 / 294
- Tree Isomorphism I1227 / 1450
- Tree Isomorphism II1020 / 1166
- Flight Route Requests578 / 713
- Critical Cities503 / 751
- Visiting Cities764 / 999
- Graph Coloring293 / 342
- Bus Companies339 / 349
- Split into Two Paths139 / 235
- Network Renovation1036 / 1359
- Forbidden Cities976 / 1260
- Creating Offices475 / 617
- New Flight Routes409 / 1038
Counting Problems
- Filled Subgrid Count I781 / 869
- Filled Subgrid Count II418 / 516
- All Letter Subgrid Count I239 / 343
- All Letter Subgrid Count II150 / 227
- Border Subgrid Count I128 / 218
- Border Subgrid Count II141 / 163
- Raab Game II145 / 165
- Empty String1915 / 2321
- Permutation Inversions1140 / 1255
- Counting Bishops445 / 498
- Counting Sequences765 / 820
- Grid Paths II849 / 1068
- Counting Permutations982 / 1107
- Grid Completion260 / 329
- Counting Reorders296 / 411
- Tournament Graph Distribution145 / 155
- Collecting Numbers Distribution153 / 160
- Functional Graph Distribution278 / 342
Additional Problems I
- Shortest Subsequence3268 / 4269
- Distinct Values Sum864 / 888
- Distinct Values Splits608 / 652
- Swap Game2256 / 2880
- Beautiful Permutation II749 / 1157
- Multiplication Table7800 / 8654
- Bubble Sort Rounds I552 / 623
- Bubble Sort Rounds II381 / 423
- Nearest Campsites I237 / 277
- Nearest Campsites II230 / 248
- Advertisement4903 / 5184
- Special Substrings1084 / 1186
- Counting LCM Arrays367 / 399
- Square Subsets284 / 313
- Subarray Sum Constraints576 / 612
- Water Containers Moves226 / 240
- Water Containers Queries260 / 275
- Stack Weights649 / 776
- Maximum Average Subarrays226 / 247
- Subsets with Fixed Average266 / 289
- Two Array Average270 / 301
- Pyramid Array859 / 1034
- Permutation Subsequence314 / 325
- Bit Inversions2559 / 2879
- Writing Numbers807 / 874
- Letter Pair Move Game234 / 324
- Maximum Building I2274 / 2374
- Sorting Methods841 / 897
- Cyclic Array1369 / 1543
- List of Sums541 / 700
Additional Problems II
- Bouncing Ball Steps316 / 348
- Bouncing Ball Cycle133 / 180
- Knight Moves Queries160 / 192
- K Subset Sums I255 / 318
- K Subset Sums II154 / 193
- Increasing Array II903 / 1031
- Food Division577 / 687
- Swap Round Sorting447 / 553
- Binary Subsequences320 / 461
- School Excursion1532 / 1618
- Coin Grid1019 / 1184
- Grid Coloring II171 / 220
- Programmers and Artists561 / 778
- Removing Digits II244 / 518
- Coin Arrangement371 / 491
- Replace with Difference171 / 204
- Grid Puzzle I604 / 662
- Grid Puzzle II586 / 641
- Bit Substrings446 / 538
- Reversal Sorting393 / 473
- Book Shop II1425 / 1622
- GCD Subsets510 / 526
- Minimum Cost Pairs179 / 225
- Same Sum Subsets157 / 297
- Mex Grid Queries926 / 1081
- Maximum Building II488 / 599
- Stick Divisions4148 / 4833
- Stick Difference104 / 334
- Coding Company1656 / 2161
- Two Stacks Sorting209 / 641