General
Introductory Problems
- Weird Algorithm37636 / 39201
- Missing Number31814 / 33722
- Repetitions28021 / 29531
- Increasing Array25903 / 27003
- Permutations23093 / 23916
- Number Spiral16228 / 17690
- Two Knights12069 / 12484
- Two Sets12957 / 14099
- Bit Strings15535 / 16395
- Trailing Zeros14650 / 15605
- Coin Piles12740 / 14086
- Palindrome Reorder11302 / 12105
- Gray Code5012 / 5693
- Tower of Hanoi4573 / 4786
- Creating Strings10237 / 10532
- Apple Division9224 / 10734
- Chessboard and Queens5501 / 5603
- Digit Queries2522 / 3128
- Grid Paths2227 / 2933
Sorting and Searching
- Distinct Numbers16522 / 17108
- Apartments11364 / 13078
- Ferris Wheel10757 / 11921
- Concert Tickets8457 / 10351
- Restaurant Customers8631 / 9486
- Movie Festival8343 / 8857
- Sum of Two Values9749 / 10763
- Maximum Subarray Sum9697 / 10096
- Stick Lengths8504 / 9029
- Missing Coin Sum4199 / 4385
- Collecting Numbers4268 / 4666
- Collecting Numbers II1696 / 2238
- Playlist6850 / 7914
- Towers6880 / 7487
- Traffic Lights5273 / 5996
- Josephus Problem I2357 / 2736
- Josephus Problem II1439 / 1870
- Nested Ranges Check1122 / 1430
- Nested Ranges Count921 / 1032
- Room Allocation4109 / 4920
- Factory Machines4707 / 5146
- Tasks and Deadlines4647 / 4759
- Reading Books3873 / 4177
- Sum of Three Values5114 / 5717
- Sum of Four Values3552 / 3983
- Nearest Smaller Values4422 / 4630
- Subarray Sums I5233 / 5829
- Subarray Sums II4925 / 5508
- Subarray Divisibility4534 / 4876
- Subarray Distinct Values1738 / 1852
- Array Division3699 / 3934
- Sliding Median2864 / 3366
- Sliding Cost1993 / 2275
- Movie Festival II2328 / 2849
- Maximum Subarray Sum II2187 / 2626
Dynamic Programming
- Dice Combinations15240 / 16165
- Minimizing Coins13254 / 14155
- Coin Combinations I12322 / 13313
- Coin Combinations II10365 / 11819
- Removing Digits11631 / 11832
- Grid Paths10709 / 11057
- Book Shop9683 / 10684
- Array Description6726 / 7586
- Counting Towers2523 / 2702
- Edit Distance7191 / 7682
- Rectangle Cutting6151 / 6741
- Money Sums7141 / 7489
- Removal Game5196 / 5682
- Two Sets II5812 / 6326
- Increasing Subsequence5802 / 6687
- Projects3813 / 4337
- Elevator Rides1588 / 2164
- Counting Tilings901 / 1006
- Counting Numbers1135 / 1280
Graph Algorithms
- Counting Rooms10329 / 11029
- Labyrinth6522 / 8085
- Building Roads8347 / 8729
- Message Route7223 / 7539
- Building Teams6938 / 7283
- Round Trip5623 / 6167
- Monsters3141 / 3975
- Shortest Routes I5732 / 6393
- Shortest Routes II4893 / 5297
- High Score2869 / 3979
- Flight Discount2957 / 3939
- Cycle Finding2734 / 3213
- Flight Routes2339 / 2585
- Round Trip II2710 / 3190
- Course Schedule3712 / 3873
- Longest Flight Route2433 / 3178
- Game Routes2752 / 3071
- Investigation1954 / 2121
- Planets Queries I1525 / 2053
- Planets Queries II789 / 962
- Planets Cycles1139 / 1273
- Road Reparation2423 / 2512
- Road Construction2476 / 2564
- Flight Routes Check2251 / 2473
- Planets and Kingdoms1905 / 1969
- Giant Pizza874 / 981
- Coin Collector1269 / 1395
- Mail Delivery1101 / 1239
- De Bruijn Sequence682 / 709
- Teleporters Path846 / 999
- Hamiltonian Flights998 / 1155
- Knight's Tour607 / 707
- Download Speed1051 / 1146
- Police Chase801 / 865
- School Dance827 / 861
- Distinct Routes504 / 714
Range Queries
- Static Range Sum Queries6837 / 7155
- Static Range Minimum Queries5208 / 5582
- Dynamic Range Sum Queries5217 / 5447
- Dynamic Range Minimum Queries4672 / 4799
- Range Xor Queries4831 / 4909
- Range Update Queries3758 / 4038
- Forest Queries3442 / 3576
- Hotel Queries2683 / 2867
- List Removals2270 / 2411
- Salary Queries1722 / 2049
- Prefix Sum Queries917 / 991
- Pizzeria Queries737 / 765
- Subarray Sum Queries1473 / 1632
- Distinct Values Queries1453 / 1693
- Increasing Array Queries371 / 435
- Forest Queries II1083 / 1151
- Range Updates and Sums1099 / 1333
- Polynomial Queries874 / 1026
- Range Queries and Copies583 / 610
Tree Algorithms
- Subordinates5492 / 5899
- Tree Matching2972 / 3600
- Tree Diameter4499 / 4791
- Tree Distances I3141 / 3443
- Tree Distances II2624 / 2738
- Company Queries I2804 / 2976
- Company Queries II2739 / 2859
- Distance Queries2675 / 2852
- Counting Paths1566 / 1669
- Subtree Queries1934 / 2070
- Path Queries1534 / 1610
- Path Queries II498 / 595
- Distinct Colors1408 / 1658
- Finding a Centroid842 / 872
- Fixed-Length Paths I429 / 480
- Fixed-Length Paths II331 / 363
Mathematics
- Josephus Queries507 / 655
- Exponentiation5348 / 5880
- Exponentiation II3743 / 4723
- Counting Divisors4229 / 4866
- Common Divisors2984 / 3457
- Sum of Divisors1700 / 2781
- Divisor Analysis676 / 938
- Prime Multiples706 / 871
- Counting Coprime Pairs463 / 572
- Binomial Coefficients2029 / 2317
- Creating Strings II1686 / 1833
- Distributing Apples1590 / 1713
- Christmas Party1428 / 1528
- Bracket Sequences I606 / 673
- Bracket Sequences II277 / 331
- Counting Necklaces305 / 329
- Counting Grids235 / 250
- Fibonacci Numbers1734 / 2222
- Throwing Dice1013 / 1106
- Graph Paths I878 / 942
- Graph Paths II738 / 765
- Dice Probability872 / 924
- Moving Robots469 / 497
- Candy Lottery639 / 656
- Inversion Probability561 / 573
- Stick Game840 / 860
- Nim Game I1029 / 1066
- Nim Game II841 / 875
- Stair Game572 / 648
- Grundy's Game236 / 301
- Another Game223 / 242
String Algorithms
- Word Combinations931 / 1485
- String Matching2011 / 2725
- Finding Borders1351 / 1543
- Finding Periods879 / 1009
- Minimal Rotation616 / 925
- Longest Palindrome772 / 1071
- Required Substring354 / 609
- Palindrome Queries220 / 266
- Finding Patterns239 / 341
- Counting Patterns232 / 279
- Pattern Positions199 / 241
- Distinct Substrings214 / 256
- Repeating Substring203 / 221
- String Functions193 / 201
- Substring Order I148 / 157
- Substring Order II105 / 128
- Substring Distribution144 / 157
Geometry
- Point Location Test1036 / 1139
- Line Segment Intersection615 / 769
- Polygon Area709 / 735
- Point in Polygon390 / 491
- Polygon Lattice Points338 / 351
- Minimum Euclidean Distance291 / 396
- Convex Hull450 / 544
Advanced Techniques
- Meet in the Middle1059 / 1422
- Hamming Distance476 / 525
- Beautiful Subgrids283 / 342
- Reachable Nodes273 / 304
- Reachability Queries218 / 248
- Cut and Paste174 / 195
- Substring Reversals154 / 162
- Reversals and Sums151 / 156
- Necessary Roads230 / 233
- Necessary Cities201 / 214
- Eulerian Subgraphs115 / 120
- Monster Game I133 / 144
- Monster Game II132 / 139
- Subarray Squares146 / 170
- Houses and Schools103 / 113
- Knuth Division126 / 145
- Apples and Bananas125 / 136
- One Bit Positions118 / 135
- Signal Processing114 / 120
- New Roads Queries162 / 218
- Dynamic Connectivity96 / 105
- Parcel Delivery91 / 105
- Task Assignment92 / 97
- Distinct Routes II83 / 97
Additional Problems
- Shortest Subsequence883 / 1154
- Counting Bits943 / 1228
- Swap Game382 / 518
- Prüfer Code382 / 407
- Acyclic Graph Edges531 / 565
- Strongly Connected Edges184 / 199
- Even Outdegree Edges174 / 203
- Multiplication Table421 / 458
- Advertisement690 / 728
- Special Substrings137 / 148
- Permutation Inversions149 / 170
- Maximum Xor Subarray520 / 563
- Movie Festival Queries244 / 281
- Chess Tournament301 / 345
- Tree Traversals265 / 299
- Network Renovation223 / 317
- Graph Girth545 / 615
- Intersection Points358 / 389
- Inverse Inversions151 / 156
- Monotone Subsequences96 / 109
- String Reorder201 / 221
- Stack Weights83 / 95
- Pyramid Array201 / 240
- Increasing Subsequence II464 / 500
- String Removals256 / 288
- Bit Inversions510 / 561
- Xor Pyramid208 / 263
- Writing Numbers240 / 262
- String Transform155 / 183
- Letter Pair Move Game30 / 41
- Maximum Building I441 / 455
- Sorting Methods241 / 256
- Cyclic Array169 / 220
- List of Sums82 / 114
- Increasing Array II106 / 120
- Food Division155 / 186
- Bit Problem270 / 293
- Swap Round Sorting108 / 141
- Binary Subsequences36 / 61
- Tree Isomorphism I206 / 262
- Counting Sequences98 / 105
- Critical Cities100 / 152
- School Excursion275 / 293
- Coin Grid161 / 196
- Robot Path79 / 146
- Programmers and Artists52 / 67
- Course Schedule II320 / 463
- Removing Digits II36 / 60
- Coin Arrangement37 / 52
- Counting Bishops54 / 60
- Grid Puzzle I79 / 90
- Grid Puzzle II55 / 60
- Empty String283 / 353
- Grid Paths215 / 273
- Bit Substrings61 / 70
- Reversal Sorting52 / 67
- Counting Reorders36 / 50
- Book Shop II235 / 261
- Network Breakdown228 / 239
- Visiting Cities177 / 234
- Missing Coin Sum Queries41 / 65
- Number Grid272 / 331
- Maximum Building II121 / 147
- Filling Trominos39 / 58
- Stick Divisions568 / 675
- Coding Company252 / 321
- Flight Route Requests134 / 149
- Two Stacks Sorting21 / 74
- Tree Isomorphism II181 / 205
- Forbidden Cities145 / 180
- Area of Rectangles219 / 254
- Grid Completion23 / 34
- Creating Offices87 / 125
- Permutations II241 / 269
- Functional Graph Distribution29 / 35
- New Flight Routes104 / 213
- Grid Path Construction20 / 32