General
Introductory Problems
- Weird Algorithm181819 / 189856
- Missing Number156851 / 163887
- Repetitions136134 / 141213
- Increasing Array128516 / 132736
- Permutations112254 / 115479
- Number Spiral79847 / 86534
- Two Knights61654 / 63445
- Two Sets66985 / 71637
- Bit Strings76087 / 80047
- Trailing Zeros70454 / 74684
- Coin Piles62745 / 68197
- Palindrome Reorder58352 / 61353
- Gray Code39919 / 44473
- Tower of Hanoi37208 / 38620
- Creating Strings49062 / 50236
- Apple Division49896 / 55848
- Chessboard and Queens30408 / 30915
- Raab Game I8371 / 9333
- Mex Grid Construction8074 / 8464
- Knight Moves Grid8155 / 8337
- Grid Coloring I6890 / 7124
- Digit Queries21345 / 24394
- String Reorder6091 / 6948
- Grid Path Description11981 / 15287
Sorting and Searching
- Distinct Numbers90469 / 97297
- Apartments67919 / 74606
- Ferris Wheel65533 / 70135
- Concert Tickets52578 / 60502
- Restaurant Customers53386 / 57259
- Movie Festival51949 / 54716
- Sum of Two Values60111 / 66706
- Maximum Subarray Sum57137 / 59455
- Stick Lengths51147 / 53313
- Missing Coin Sum39274 / 40600
- Collecting Numbers40181 / 42746
- Collecting Numbers II17789 / 22048
- Playlist40155 / 45359
- Towers40091 / 42740
- Traffic Lights31168 / 34591
- Distinct Values Subarrays11289 / 12557
- Distinct Values Subsequences8696 / 9427
- Josephus Problem I24416 / 26633
- Josephus Problem II13249 / 18165
- Nested Ranges Check14591 / 16446
- Nested Ranges Count9754 / 11370
- Room Allocation23771 / 26981
- Factory Machines34563 / 37244
- Tasks and Deadlines27479 / 28000
- Reading Books22351 / 23800
- Sum of Three Values32056 / 35182
- Sum of Four Values19969 / 21999
- Nearest Smaller Values26906 / 27755
- Subarray Sums I35690 / 37787
- Subarray Sums II32602 / 38097
- Subarray Divisibility29404 / 31781
- Distinct Values Subarrays II17987 / 19515
- Array Division27870 / 29197
- Movie Festival II15205 / 18047
- Maximum Subarray Sum II14175 / 16660
Dynamic Programming
- Dice Combinations94814 / 99998
- Minimizing Coins82014 / 87723
- Coin Combinations I74949 / 80687
- Coin Combinations II63663 / 71433
- Removing Digits70702 / 72076
- Grid Paths I66377 / 68125
- Book Shop59965 / 65480
- Array Description44460 / 48923
- Counting Towers27834 / 29350
- Edit Distance44163 / 46438
- Longest Common Subsequence16148 / 16664
- Rectangle Cutting36429 / 39556
- Minimal Grid Path7646 / 12451
- Money Sums43041 / 44552
- Removal Game26896 / 34440
- Two Sets II34001 / 36302
- Mountain Range5332 / 8936
- Increasing Subsequence34486 / 38575
- Projects24402 / 27053
- Elevator Rides16092 / 19823
- Counting Tilings9431 / 10174
- Counting Numbers14131 / 15593
- Increasing Subsequence II6520 / 7629
Graph Algorithms
- Counting Rooms66158 / 69207
- Labyrinth47087 / 55124
- Building Roads57925 / 59832
- Message Route50266 / 52049
- Building Teams47443 / 49712
- Round Trip37634 / 40639
- Monsters26869 / 30918
- Shortest Routes I41640 / 45333
- Shortest Routes II33535 / 37192
- High Score21691 / 29026
- Flight Discount27727 / 31751
- Cycle Finding19603 / 23318
- Flight Routes19101 / 21023
- Round Trip II21190 / 23495
- Course Schedule27969 / 29324
- Longest Flight Route20565 / 24592
- Game Routes22337 / 23662
- Investigation17048 / 18154
- Planets Queries I14800 / 16994
- Planets Queries II5389 / 6670
- Planets Cycles8915 / 9828
- Road Reparation21829 / 22657
- Road Construction23786 / 24484
- Flight Routes Check18894 / 20268
- Planets and Kingdoms15492 / 16103
- Giant Pizza6515 / 7103
- Coin Collector10339 / 11284
- Mail Delivery8149 / 8831
- De Bruijn Sequence4293 / 4484
- Teleporters Path6306 / 7069
- Hamiltonian Flights9698 / 10934
- Knight's Tour3616 / 4308
- Download Speed6263 / 8109
- Police Chase4999 / 5534
- School Dance5507 / 5793
- Distinct Routes3885 / 4948
Range Queries
- Static Range Sum Queries46402 / 48419
- Static Range Minimum Queries31831 / 34043
- Dynamic Range Sum Queries33189 / 34585
- Dynamic Range Minimum Queries29952 / 30631
- Range Xor Queries30477 / 30872
- Range Update Queries24759 / 26401
- Forest Queries25371 / 26222
- Hotel Queries18111 / 19086
- List Removals15069 / 15764
- Salary Queries11722 / 14400
- Prefix Sum Queries9800 / 10500
- Pizzeria Queries7832 / 8090
- Visible Buildings Queries2515 / 2722
- Range Interval Queries1907 / 2524
- Subarray Sum Queries9012 / 9702
- Subarray Sum Queries II2897 / 2974
- Distinct Values Queries8517 / 10283
- Distinct Values Queries II1578 / 1778
- Increasing Array Queries3255 / 3688
- Movie Festival Queries1846 / 2019
- Forest Queries II5252 / 5616
- Range Updates and Sums7499 / 8733
- Polynomial Queries5481 / 6355
- Range Queries and Copies3873 / 4116
- Missing Coin Sum Queries948 / 1285
Tree Algorithms
- Subordinates38056 / 40562
- Tree Matching22174 / 25450
- Tree Diameter31209 / 32896
- Tree Distances I24311 / 25940
- Tree Distances II19846 / 20705
- Company Queries I22275 / 23346
- Company Queries II20823 / 21829
- Distance Queries18753 / 20006
- Counting Paths11935 / 12566
- Subtree Queries13938 / 14783
- Path Queries11277 / 11875
- Path Queries II4749 / 6885
- Distinct Colors10796 / 11793
- Finding a Centroid8763 / 9097
- Fixed-Length Paths I4422 / 5515
- Fixed-Length Paths II2187 / 3736
Mathematics
- Josephus Queries6098 / 7572
- Exponentiation29456 / 31325
- Exponentiation II20515 / 24264
- Counting Divisors27049 / 30396
- Common Divisors17356 / 19952
- Sum of Divisors9946 / 14444
- Divisor Analysis6816 / 8966
- Prime Multiples7938 / 9152
- Counting Coprime Pairs5265 / 6039
- Next Prime2926 / 3316
- Binomial Coefficients12724 / 14007
- Creating Strings II10503 / 11047
- Distributing Apples10023 / 10738
- Christmas Party8380 / 8916
- Permutation Order1416 / 1451
- Permutation Rounds2087 / 2284
- Bracket Sequences I5582 / 6039
- Bracket Sequences II2995 / 3391
- Counting Necklaces2727 / 2938
- Counting Grids2305 / 2439
- Fibonacci Numbers8359 / 10366
- Throwing Dice4382 / 4736
- Graph Paths I4260 / 4532
- Graph Paths II3572 / 3734
- System of Linear Equations709 / 763
- Sum of Four Squares1017 / 1207
- Triangle Number Sums897 / 1067
- Dice Probability3742 / 4009
- Moving Robots1949 / 2049
- Candy Lottery2089 / 3757
- Inversion Probability636 / 2754
- Stick Game4277 / 4374
- Nim Game I5706 / 5911
- Nim Game II4523 / 4695
- Stair Game3082 / 3331
- Grundy's Game2157 / 2814
- Another Game2441 / 2617
String Algorithms
- Word Combinations7445 / 10464
- String Matching14047 / 18514
- Finding Borders10374 / 11263
- Finding Periods7444 / 8349
- Minimal Rotation3732 / 5389
- Longest Palindrome5453 / 7028
- All Palindromes1073 / 1192
- Required Substring2081 / 3072
- Palindrome Queries2554 / 2937
- Finding Patterns2466 / 3371
- Counting Patterns2331 / 2815
- Pattern Positions1973 / 2355
- Distinct Substrings2189 / 2582
- Distinct Subsequences1416 / 1493
- Repeating Substring2348 / 2679
- String Functions2056 / 2148
- Inverse Suffix Array410 / 464
- String Transform714 / 841
- Substring Order I1496 / 1645
- Substring Order II1016 / 1291
- Substring Distribution1388 / 1497
Geometry
- Point Location Test8854 / 9799
- Line Segment Intersection5263 / 6514
- Polygon Area6027 / 6341
- Point in Polygon3393 / 4239
- Polygon Lattice Points2743 / 2927
- Minimum Euclidean Distance2436 / 3379
- Convex Hull4036 / 4761
- Maximum Manhattan Distances934 / 974
- All Manhattan Distances982 / 1079
- Intersection Points2432 / 2619
- Line Segments Trace I503 / 520
- Line Segments Trace II420 / 439
- Lines and Queries I545 / 570
- Lines and Queries II491 / 512
- Area of Rectangles1436 / 1594
- Robot Path399 / 715
Advanced Techniques
- Meet in the Middle8596 / 11472
- Hamming Distance3772 / 4114
- Corner Subgrid Check374 / 758
- Corner Subgrid Count2542 / 2893
- Reachable Nodes2677 / 2864
- Reachability Queries1802 / 2107
- Cut and Paste1851 / 2038
- Substring Reversals1633 / 1758
- Reversals and Sums1662 / 1772
- Necessary Roads2435 / 2494
- Necessary Cities2254 / 2350
- Eulerian Subgraphs954 / 1003
- Monster Game I1440 / 1589
- Monster Game II1268 / 1351
- Subarray Squares1800 / 2078
- Houses and Schools975 / 1147
- Knuth Division1157 / 1296
- Apples and Bananas1366 / 1472
- One Bit Positions1027 / 1115
- Signal Processing1026 / 1095
- New Roads Queries2712 / 3237
- Dynamic Connectivity1244 / 1386
- Parcel Delivery990 / 1076
- Task Assignment1142 / 1229
- Distinct Routes II751 / 843
Sliding Window Problems
- Sliding Window Sum8632 / 8909
- Sliding Window Minimum6506 / 7389
- Sliding Window Xor6366 / 6449
- Sliding Window Or2898 / 4744
- Sliding Window Distinct Values4570 / 5270
- Sliding Window Mode3535 / 3736
- Sliding Window Mex3338 / 3507
- Sliding Window Median15544 / 17637
- Sliding Window Cost10152 / 11647
- Sliding Window Inversions1792 / 1891
- Sliding Window Advertisement351 / 541
Interactive Problems
- Hidden Integer3062 / 3200
- Hidden Permutation1373 / 1583
- K-th Highest Score631 / 760
- Permuted Binary Strings730 / 749
- Colored Chairs687 / 729
- Inversion Sorting407 / 455
Bitwise Operations
- Counting Bits6549 / 8383
- Maximum Xor Subarray3857 / 4403
- Maximum Xor Subset1503 / 1651
- Number of Subset Xors1306 / 1336
- K Subset Xors681 / 793
- All Subarray Xors412 / 637
- Xor Pyramid Peak2561 / 3054
- Xor Pyramid Diagonal473 / 529
- Xor Pyramid Row403 / 469
- SOS Bit Problem2685 / 2839
- And Subset Count662 / 688
Construction Problems
- Inverse Inversions2164 / 2309
- Monotone Subsequences1310 / 1547
- Third Permutation588 / 721
- Permutation Prime Sums592 / 634
- Chess Tournament1427 / 1637
- Distinct Sums Grid219 / 321
- Filling Trominos323 / 547
- Grid Path Construction181 / 510
Advanced Graph Problems
- Nearest Shops1047 / 1333
- Prüfer Code1790 / 1913
- Tree Traversals1468 / 1604
- Course Schedule II2465 / 3437
- Acyclic Graph Edges2531 / 2678
- Strongly Connected Edges1869 / 2155
- Even Outdegree Edges1630 / 1893
- Graph Girth4113 / 4625
- Fixed Length Walk Queries517 / 569
- Transfer Speeds Sum583 / 601
- MST Edge Check955 / 1028
- MST Edge Set Check400 / 448
- MST Edge Cost560 / 582
- Network Breakdown1399 / 1515
- Tree Coin Collecting I497 / 537
- Tree Coin Collecting II289 / 328
- Tree Isomorphism I1269 / 1491
- Tree Isomorphism II1049 / 1196
- Flight Route Requests605 / 748
- Critical Cities525 / 782
- Visiting Cities798 / 1032
- Graph Coloring321 / 373
- Bus Companies374 / 384
- Split into Two Paths148 / 249
- Network Renovation1070 / 1396
- Forbidden Cities1021 / 1306
- Creating Offices494 / 641
- New Flight Routes427 / 1075
Counting Problems
- Filled Subgrid Count I853 / 949
- Filled Subgrid Count II466 / 568
- All Letter Subgrid Count I266 / 374
- All Letter Subgrid Count II169 / 246
- Border Subgrid Count I137 / 230
- Border Subgrid Count II152 / 174
- Raab Game II158 / 178
- Empty String1986 / 2400
- Permutation Inversions1163 / 1280
- Counting Bishops466 / 518
- Counting Sequences792 / 847
- Grid Paths II872 / 1097
- Counting Permutations1012 / 1137
- Grid Completion277 / 344
- Counting Reorders313 / 428
- Tournament Graph Distribution158 / 168
- Collecting Numbers Distribution162 / 170
- Functional Graph Distribution289 / 351
Additional Problems I
- Shortest Subsequence3353 / 4355
- Distinct Values Sum918 / 943
- Distinct Values Splits651 / 696
- Swap Game2308 / 2937
- Beautiful Permutation II832 / 1264
- Multiplication Table8016 / 8891
- Bubble Sort Rounds I596 / 671
- Bubble Sort Rounds II415 / 459
- Nearest Campsites I260 / 303
- Nearest Campsites II253 / 271
- Advertisement5043 / 5327
- Special Substrings1114 / 1220
- Counting LCM Arrays404 / 436
- Square Subsets311 / 344
- Subarray Sum Constraints645 / 685
- Water Containers Moves251 / 265
- Water Containers Queries288 / 302
- Stack Weights670 / 798
- Maximum Average Subarrays245 / 269
- Subsets with Fixed Average292 / 317
- Two Array Average296 / 328
- Pyramid Array905 / 1088
- Permutation Subsequence341 / 354
- Bit Inversions2637 / 2959
- Writing Numbers833 / 899
- Letter Pair Move Game245 / 335
- Maximum Building I2351 / 2453
- Sorting Methods869 / 926
- Cyclic Array1430 / 1608
- List of Sums563 / 725
Additional Problems II
- Bouncing Ball Steps348 / 382
- Bouncing Ball Cycle148 / 198
- Knight Moves Queries180 / 214
- K Subset Sums I280 / 344
- K Subset Sums II170 / 208
- Increasing Array II941 / 1073
- Food Division599 / 710
- Swap Round Sorting466 / 576
- Binary Subsequences332 / 473
- School Excursion1564 / 1653
- Coin Grid1069 / 1235
- Grid Coloring II187 / 240
- Programmers and Artists582 / 800
- Removing Digits II255 / 530
- Coin Arrangement392 / 514
- Replace with Difference192 / 225
- Grid Puzzle I632 / 690
- Grid Puzzle II617 / 673
- Bit Substrings467 / 559
- Reversal Sorting408 / 489
- Book Shop II1479 / 1682
- GCD Subsets553 / 569
- Minimum Cost Pairs196 / 241
- Same Sum Subsets172 / 323
- Mex Grid Queries951 / 1108
- Maximum Building II509 / 621
- Stick Divisions4249 / 4946
- Stick Difference117 / 355
- Coding Company1706 / 2217
- Two Stacks Sorting225 / 671