General
Introductory Problems
- Weird Algorithm98385 / 103057
- Missing Number83720 / 88318
- Repetitions73088 / 76578
- Increasing Array68226 / 71114
- Permutations59982 / 62042
- Number Spiral42429 / 46279
- Two Knights31840 / 32987
- Two Sets34398 / 37405
- Bit Strings40081 / 42335
- Trailing Zeros37543 / 40155
- Coin Piles33043 / 36465
- Palindrome Reorder30177 / 32180
- Gray Code18755 / 21447
- Tower of Hanoi17490 / 18243
- Creating Strings26017 / 26813
- Apple Division25236 / 28980
- Chessboard and Queens14994 / 15309
- Digit Queries10102 / 12157
- Grid Paths6245 / 7980
Sorting and Searching
- Distinct Numbers46031 / 50499
- Apartments33555 / 38142
- Ferris Wheel31920 / 34925
- Concert Tickets25532 / 30424
- Restaurant Customers26246 / 28657
- Movie Festival24690 / 26410
- Sum of Two Values29107 / 33229
- Maximum Subarray Sum28720 / 30221
- Stick Lengths25434 / 26877
- Missing Coin Sum17734 / 18462
- Collecting Numbers18386 / 19919
- Collecting Numbers II7323 / 9588
- Playlist19137 / 22330
- Towers19618 / 21225
- Traffic Lights15372 / 17334
- Josephus Problem I10417 / 11824
- Josephus Problem II6045 / 7886
- Nested Ranges Check5930 / 6977
- Nested Ranges Count4232 / 4884
- Room Allocation11172 / 13020
- Factory Machines14343 / 16093
- Tasks and Deadlines12975 / 13290
- Reading Books10359 / 11131
- Sum of Three Values15101 / 17124
- Sum of Four Values9575 / 10840
- Nearest Smaller Values12793 / 13303
- Subarray Sums I16486 / 17763
- Subarray Sums II15252 / 17434
- Subarray Divisibility13392 / 14786
- Subarray Distinct Values7591 / 8227
- Array Division12217 / 12973
- Sliding Window Median8071 / 9225
- Sliding Window Cost5648 / 6510
- Movie Festival II6972 / 8463
- Maximum Subarray Sum II6379 / 7661
Dynamic Programming
- Dice Combinations45402 / 48396
- Minimizing Coins39074 / 42318
- Coin Combinations I35954 / 39239
- Coin Combinations II30167 / 34655
- Removing Digits33373 / 34235
- Grid Paths31729 / 32802
- Book Shop27881 / 31206
- Array Description20142 / 22741
- Counting Towers11443 / 12151
- Edit Distance20912 / 22245
- Rectangle Cutting17457 / 19149
- Money Sums20819 / 21750
- Removal Game14878 / 16567
- Two Sets II16419 / 17934
- Increasing Subsequence16890 / 19196
- Projects11366 / 12913
- Elevator Rides6829 / 8795
- Counting Tilings3902 / 4297
- Counting Numbers5268 / 6017
Graph Algorithms
- Counting Rooms31009 / 33017
- Labyrinth20336 / 25279
- Building Roads26835 / 27981
- Message Route22793 / 23911
- Building Teams21883 / 23000
- Round Trip16987 / 18773
- Monsters10679 / 13166
- Shortest Routes I18243 / 20742
- Shortest Routes II15374 / 16858
- High Score7676 / 12665
- Flight Discount10716 / 13148
- Cycle Finding7972 / 10055
- Flight Routes7421 / 8371
- Round Trip II8906 / 10250
- Course Schedule12364 / 12911
- Longest Flight Route7621 / 10254
- Game Routes8942 / 9861
- Investigation6538 / 7113
- Planets Queries I5540 / 6778
- Planets Queries II2220 / 2759
- Planets Cycles3700 / 4166
- Road Reparation8843 / 9299
- Road Construction9316 / 9687
- Flight Routes Check7945 / 8784
- Planets and Kingdoms6403 / 6682
- Giant Pizza2578 / 2905
- Coin Collector3985 / 4527
- Mail Delivery3446 / 3843
- De Bruijn Sequence1859 / 1960
- Teleporters Path2738 / 3071
- Hamiltonian Flights3826 / 4366
- Knight's Tour1617 / 1918
- Download Speed2651 / 3777
- Police Chase2166 / 2489
- School Dance2390 / 2550
- Distinct Routes1529 / 2093
Range Queries
- Static Range Sum Queries21082 / 22076
- Static Range Minimum Queries15676 / 16794
- Dynamic Range Sum Queries16151 / 16910
- Dynamic Range Minimum Queries14694 / 15087
- Range Xor Queries14860 / 15086
- Range Update Queries11826 / 12759
- Forest Queries11616 / 12100
- Hotel Queries8474 / 8958
- List Removals7046 / 7448
- Salary Queries5206 / 6312
- Prefix Sum Queries4202 / 4604
- Pizzeria Queries3419 / 3549
- Subarray Sum Queries4367 / 4897
- Distinct Values Queries4092 / 4992
- Increasing Array Queries1485 / 1709
- Forest Queries II2825 / 3062
- Range Updates and Sums3378 / 4133
- Polynomial Queries2592 / 3047
- Range Queries and Copies1824 / 1979
Tree Algorithms
- Subordinates17465 / 18906
- Tree Matching9776 / 11543
- Tree Diameter14471 / 15519
- Tree Distances I10732 / 11652
- Tree Distances II8790 / 9185
- Company Queries I9701 / 10283
- Company Queries II9106 / 9628
- Distance Queries8508 / 9136
- Counting Paths5077 / 5443
- Subtree Queries6244 / 6694
- Path Queries4992 / 5278
- Path Queries II1737 / 2917
- Distinct Colors4747 / 5359
- Finding a Centroid3885 / 4067
- Fixed-Length Paths I1591 / 2303
- Fixed-Length Paths II656 / 1572
Mathematics
- Josephus Queries2530 / 3201
- Exponentiation14747 / 15941
- Exponentiation II10530 / 12987
- Counting Divisors12674 / 14530
- Common Divisors8515 / 10222
- Sum of Divisors4856 / 7447
- Divisor Analysis3150 / 4210
- Prime Multiples3423 / 4062
- Counting Coprime Pairs2159 / 2558
- Binomial Coefficients5954 / 6751
- Creating Strings II4992 / 5347
- Distributing Apples4880 / 5290
- Christmas Party3779 / 4112
- Bracket Sequences I2563 / 2844
- Bracket Sequences II1318 / 1524
- Counting Necklaces1275 / 1387
- Counting Grids1026 / 1098
- Fibonacci Numbers4354 / 5605
- Throwing Dice2355 / 2564
- Graph Paths I2153 / 2321
- Graph Paths II1807 / 1892
- Dice Probability2056 / 2184
- Moving Robots1032 / 1102
- Candy Lottery1585 / 1630
- Inversion Probability457 / 1421
- Stick Game2112 / 2172
- Nim Game I2657 / 2767
- Nim Game II2158 / 2254
- Stair Game1499 / 1645
- Grundy's Game958 / 1240
- Another Game1095 / 1193
String Algorithms
- Word Combinations3107 / 4767
- String Matching6197 / 8940
- Finding Borders4606 / 5164
- Finding Periods3144 / 3576
- Minimal Rotation1570 / 2574
- Longest Palindrome2367 / 3321
- Required Substring919 / 1503
- Palindrome Queries1141 / 1366
- Finding Patterns983 / 1454
- Counting Patterns886 / 1176
- Pattern Positions785 / 1006
- Distinct Substrings937 / 1130
- Repeating Substring955 / 1075
- String Functions908 / 958
- Substring Order I673 / 723
- Substring Order II442 / 561
- Substring Distribution611 / 669
Geometry
- Point Location Test4128 / 4766
- Line Segment Intersection2501 / 3271
- Polygon Area2999 / 3229
- Point in Polygon1648 / 2104
- Polygon Lattice Points1411 / 1463
- Minimum Euclidean Distance1282 / 1766
- Convex Hull2067 / 2517
Advanced Techniques
- Meet in the Middle3566 / 5520
- Hamming Distance1966 / 2131
- Beautiful Subgrids1386 / 1560
- Reachable Nodes1395 / 1515
- Reachability Queries962 / 1142
- Cut and Paste906 / 1021
- Substring Reversals791 / 869
- Reversals and Sums791 / 864
- Necessary Roads1199 / 1235
- Necessary Cities1119 / 1177
- Eulerian Subgraphs504 / 533
- Monster Game I728 / 801
- Monster Game II652 / 707
- Subarray Squares722 / 852
- Houses and Schools474 / 546
- Knuth Division553 / 626
- Apples and Bananas514 / 571
- One Bit Positions488 / 543
- Signal Processing456 / 498
- New Roads Queries1199 / 1463
- Dynamic Connectivity545 / 620
- Parcel Delivery438 / 499
- Task Assignment416 / 452
- Distinct Routes II349 / 407
Additional Problems
- Shortest Subsequence1973 / 2539
- Counting Bits2269 / 2936
- Swap Game1229 / 1584
- Prüfer Code873 / 969
- Acyclic Graph Edges1357 / 1448
- Strongly Connected Edges845 / 932
- Even Outdegree Edges769 / 899
- Multiplication Table2915 / 3329
- Advertisement2526 / 2695
- Special Substrings576 / 624
- Permutation Inversions621 / 688
- Maximum Xor Subarray1452 / 1589
- Movie Festival Queries643 / 719
- Chess Tournament723 / 827
- Tree Traversals696 / 782
- Network Renovation614 / 815
- Graph Girth1879 / 2190
- Intersection Points1142 / 1227
- Inverse Inversions631 / 662
- Monotone Subsequences427 / 474
- String Reorder506 / 559
- Stack Weights369 / 430
- Pyramid Array497 / 591
- Increasing Subsequence II1450 / 1572
- String Removals632 / 687
- Bit Inversions1465 / 1713
- Xor Pyramid776 / 987
- Writing Numbers508 / 549
- String Transform326 / 405
- Letter Pair Move Game114 / 170
- Maximum Building I1326 / 1390
- Sorting Methods529 / 566
- Cyclic Array657 / 757
- List of Sums299 / 401
- Increasing Array II496 / 565
- Food Division365 / 432
- Bit Problem953 / 1029
- Swap Round Sorting282 / 351
- Binary Subsequences148 / 235
- Tree Isomorphism I660 / 767
- Counting Sequences378 / 408
- Critical Cities250 / 396
- School Excursion853 / 911
- Coin Grid463 / 552
- Robot Path197 / 340
- Programmers and Artists313 / 402
- Course Schedule II1022 / 1454
- Removing Digits II126 / 269
- Coin Arrangement214 / 282
- Counting Bishops224 / 252
- Grid Puzzle I327 / 357
- Grid Puzzle II241 / 270
- Empty String918 / 1105
- Grid Paths501 / 622
- Bit Substrings224 / 279
- Reversal Sorting214 / 260
- Counting Reorders131 / 198
- Book Shop II650 / 739
- Network Breakdown613 / 653
- Visiting Cities451 / 586
- Missing Coin Sum Queries250 / 331
- Number Grid589 / 705
- Maximum Building II291 / 358
- Filling Trominos125 / 212
- Stick Divisions2337 / 2776
- Coding Company884 / 1129
- Flight Route Requests285 / 346
- Two Stacks Sorting94 / 324
- Tree Isomorphism II543 / 632
- Forbidden Cities453 / 593
- Area of Rectangles679 / 767
- Grid Completion132 / 174
- Creating Offices256 / 334
- Permutations II573 / 656
- Functional Graph Distribution146 / 183
- New Flight Routes202 / 485
- Grid Path Construction63 / 233