General
Introductory Problems
- Weird Algorithm99912 / 104666
- Missing Number85064 / 89738
- Repetitions74298 / 77825
- Increasing Array69382 / 72298
- Permutations61008 / 63093
- Number Spiral43169 / 47094
- Two Knights32375 / 33538
- Two Sets35000 / 38041
- Bit Strings40766 / 43054
- Trailing Zeros38139 / 40798
- Coin Piles33595 / 37084
- Palindrome Reorder30707 / 32740
- Gray Code19132 / 21880
- Tower of Hanoi17833 / 18599
- Creating Strings26477 / 27285
- Apple Division25703 / 29476
- Chessboard and Queens15263 / 15581
- Digit Queries10321 / 12414
- Grid Paths6361 / 8139
Sorting and Searching
- Distinct Numbers46917 / 51425
- Apartments34215 / 38882
- Ferris Wheel32550 / 35608
- Concert Tickets26069 / 31057
- Restaurant Customers26801 / 29256
- Movie Festival25187 / 26935
- Sum of Two Values29711 / 33905
- Maximum Subarray Sum29270 / 30794
- Stick Lengths25937 / 27395
- Missing Coin Sum18130 / 18874
- Collecting Numbers18791 / 20357
- Collecting Numbers II7484 / 9802
- Playlist19469 / 22719
- Towers19961 / 21609
- Traffic Lights15652 / 17640
- Josephus Problem I10678 / 12108
- Josephus Problem II6169 / 8059
- Nested Ranges Check6060 / 7132
- Nested Ranges Count4311 / 4986
- Room Allocation11394 / 13268
- Factory Machines14770 / 16553
- Tasks and Deadlines13235 / 13550
- Reading Books10551 / 11341
- Sum of Three Values15396 / 17461
- Sum of Four Values9764 / 11042
- Nearest Smaller Values13017 / 13534
- Subarray Sums I16839 / 18133
- Subarray Sums II15560 / 17763
- Subarray Divisibility13643 / 15056
- Subarray Distinct Values7788 / 8434
- Array Division12493 / 13267
- Sliding Window Median8267 / 9459
- Sliding Window Cost5745 / 6617
- Movie Festival II7108 / 8615
- Maximum Subarray Sum II6515 / 7823
Dynamic Programming
- Dice Combinations46288 / 49329
- Minimizing Coins39837 / 43138
- Coin Combinations I36616 / 39962
- Coin Combinations II30745 / 35300
- Removing Digits33991 / 34871
- Grid Paths32327 / 33428
- Book Shop28434 / 31807
- Array Description20542 / 23179
- Counting Towers11708 / 12428
- Edit Distance21295 / 22653
- Rectangle Cutting17762 / 19492
- Money Sums21205 / 22159
- Removal Game15136 / 16846
- Two Sets II16721 / 18268
- Increasing Subsequence17181 / 19535
- Projects11540 / 13112
- Elevator Rides6987 / 8982
- Counting Tilings3999 / 4403
- Counting Numbers5387 / 6145
Graph Algorithms
- Counting Rooms31580 / 33616
- Labyrinth20725 / 25765
- Building Roads27334 / 28507
- Message Route23230 / 24367
- Building Teams22289 / 23429
- Round Trip17303 / 19113
- Monsters10921 / 13452
- Shortest Routes I18567 / 21214
- Shortest Routes II15673 / 17197
- High Score7883 / 12928
- Flight Discount10965 / 13442
- Cycle Finding8134 / 10251
- Flight Routes7563 / 8531
- Round Trip II9095 / 10450
- Course Schedule12596 / 13170
- Longest Flight Route7809 / 10477
- Game Routes9100 / 10031
- Investigation6680 / 7271
- Planets Queries I5652 / 6900
- Planets Queries II2262 / 2809
- Planets Cycles3779 / 4259
- Road Reparation9033 / 9503
- Road Construction9528 / 9904
- Flight Routes Check8100 / 8958
- Planets and Kingdoms6529 / 6815
- Giant Pizza2666 / 3001
- Coin Collector4073 / 4619
- Mail Delivery3535 / 3937
- De Bruijn Sequence1902 / 2004
- Teleporters Path2803 / 3138
- Hamiltonian Flights3917 / 4461
- Knight's Tour1654 / 1962
- Download Speed2761 / 3892
- Police Chase2217 / 2545
- School Dance2439 / 2601
- Distinct Routes1589 / 2160
Range Queries
- Static Range Sum Queries21529 / 22536
- Static Range Minimum Queries16002 / 17136
- Dynamic Range Sum Queries16491 / 17269
- Dynamic Range Minimum Queries15008 / 15420
- Range Xor Queries15160 / 15396
- Range Update Queries12096 / 13046
- Forest Queries11839 / 12329
- Hotel Queries8666 / 9163
- List Removals7221 / 7635
- Salary Queries5343 / 6491
- Prefix Sum Queries4292 / 4702
- Pizzeria Queries3509 / 3641
- Subarray Sum Queries4459 / 4988
- Distinct Values Queries4180 / 5096
- Increasing Array Queries1512 / 1743
- Forest Queries II2872 / 3113
- Range Updates and Sums3444 / 4221
- Polynomial Queries2632 / 3105
- Range Queries and Copies1852 / 2010
Tree Algorithms
- Subordinates17810 / 19275
- Tree Matching9946 / 11753
- Tree Diameter14736 / 15787
- Tree Distances I10930 / 11871
- Tree Distances II8957 / 9365
- Company Queries I9889 / 10482
- Company Queries II9280 / 9811
- Distance Queries8665 / 9309
- Counting Paths5173 / 5551
- Subtree Queries6395 / 6853
- Path Queries5105 / 5401
- Path Queries II1817 / 3014
- Distinct Colors4865 / 5480
- Finding a Centroid3980 / 4164
- Fixed-Length Paths I1675 / 2393
- Fixed-Length Paths II688 / 1618
Mathematics
- Josephus Queries2577 / 3264
- Exponentiation14995 / 16223
- Exponentiation II10739 / 13221
- Counting Divisors12958 / 14861
- Common Divisors8679 / 10425
- Sum of Divisors4935 / 7567
- Divisor Analysis3214 / 4297
- Prime Multiples3496 / 4148
- Counting Coprime Pairs2200 / 2608
- Binomial Coefficients6056 / 6868
- Creating Strings II5081 / 5441
- Distributing Apples4963 / 5391
- Christmas Party3845 / 4181
- Bracket Sequences I2617 / 2904
- Bracket Sequences II1347 / 1558
- Counting Necklaces1302 / 1419
- Counting Grids1049 / 1123
- Fibonacci Numbers4434 / 5717
- Throwing Dice2405 / 2615
- Graph Paths I2197 / 2371
- Graph Paths II1839 / 1930
- Dice Probability2094 / 2223
- Moving Robots1051 / 1122
- Candy Lottery1621 / 1667
- Inversion Probability482 / 1449
- Stick Game2156 / 2217
- Nim Game I2721 / 2842
- Nim Game II2220 / 2321
- Stair Game1529 / 1677
- Grundy's Game987 / 1274
- Another Game1123 / 1225
String Algorithms
- Word Combinations3185 / 4883
- String Matching6397 / 9158
- Finding Borders4693 / 5254
- Finding Periods3215 / 3659
- Minimal Rotation1598 / 2618
- Longest Palindrome2429 / 3400
- Required Substring948 / 1538
- Palindrome Queries1168 / 1406
- Finding Patterns1014 / 1494
- Counting Patterns914 / 1210
- Pattern Positions806 / 1029
- Distinct Substrings964 / 1162
- Repeating Substring976 / 1100
- String Functions931 / 984
- Substring Order I693 / 744
- Substring Order II450 / 572
- Substring Distribution627 / 688
Geometry
- Point Location Test4234 / 4879
- Line Segment Intersection2572 / 3357
- Polygon Area3078 / 3310
- Point in Polygon1691 / 2159
- Polygon Lattice Points1444 / 1501
- Minimum Euclidean Distance1319 / 1805
- Convex Hull2133 / 2587
Advanced Techniques
- Meet in the Middle3656 / 5627
- Hamming Distance2007 / 2175
- Beautiful Subgrids1417 / 1593
- Reachable Nodes1432 / 1553
- Reachability Queries988 / 1173
- Cut and Paste935 / 1055
- Substring Reversals822 / 904
- Reversals and Sums821 / 899
- Necessary Roads1230 / 1267
- Necessary Cities1148 / 1207
- Eulerian Subgraphs515 / 545
- Monster Game I746 / 821
- Monster Game II668 / 724
- Subarray Squares739 / 872
- Houses and Schools483 / 559
- Knuth Division566 / 641
- Apples and Bananas526 / 583
- One Bit Positions504 / 561
- Signal Processing469 / 514
- New Roads Queries1226 / 1495
- Dynamic Connectivity562 / 644
- Parcel Delivery446 / 508
- Task Assignment430 / 469
- Distinct Routes II355 / 414
Additional Problems
- Shortest Subsequence2021 / 2593
- Counting Bits2307 / 2981
- Swap Game1269 / 1629
- Prüfer Code890 / 986
- Acyclic Graph Edges1385 / 1480
- Strongly Connected Edges873 / 961
- Even Outdegree Edges793 / 926
- Multiplication Table3015 / 3445
- Advertisement2585 / 2756
- Special Substrings598 / 648
- Permutation Inversions639 / 709
- Maximum Xor Subarray1485 / 1629
- Movie Festival Queries655 / 733
- Chess Tournament739 / 845
- Tree Traversals709 / 797
- Network Renovation627 / 830
- Graph Girth1924 / 2245
- Intersection Points1174 / 1265
- Inverse Inversions647 / 678
- Monotone Subsequences437 / 487
- String Reorder516 / 570
- Stack Weights376 / 440
- Pyramid Array501 / 599
- Increasing Subsequence II1489 / 1616
- String Removals646 / 702
- Bit Inversions1512 / 1761
- Xor Pyramid791 / 1011
- Writing Numbers510 / 554
- String Transform329 / 410
- Letter Pair Move Game119 / 176
- Maximum Building I1348 / 1415
- Sorting Methods539 / 578
- Cyclic Array674 / 775
- List of Sums302 / 406
- Increasing Array II513 / 585
- Food Division369 / 438
- Bit Problem984 / 1062
- Swap Round Sorting288 / 358
- Binary Subsequences149 / 239
- Tree Isomorphism I667 / 776
- Counting Sequences384 / 415
- Critical Cities258 / 403
- School Excursion875 / 934
- Coin Grid471 / 563
- Robot Path199 / 345
- Programmers and Artists317 / 407
- Course Schedule II1044 / 1481
- Removing Digits II128 / 275
- Coin Arrangement216 / 286
- Counting Bishops228 / 257
- Grid Puzzle I334 / 365
- Grid Puzzle II247 / 277
- Empty String939 / 1130
- Grid Paths508 / 633
- Bit Substrings237 / 295
- Reversal Sorting219 / 267
- Counting Reorders133 / 201
- Book Shop II661 / 753
- Network Breakdown627 / 667
- Visiting Cities461 / 601
- Missing Coin Sum Queries256 / 343
- Number Grid596 / 715
- Maximum Building II295 / 363
- Filling Trominos128 / 219
- Stick Divisions2393 / 2835
- Coding Company905 / 1154
- Flight Route Requests296 / 359
- Two Stacks Sorting95 / 329
- Tree Isomorphism II549 / 639
- Forbidden Cities457 / 599
- Area of Rectangles692 / 780
- Grid Completion133 / 177
- Creating Offices259 / 337
- Permutations II583 / 667
- Functional Graph Distribution147 / 185
- New Flight Routes205 / 496
- Grid Path Construction67 / 241