General
Introductory Problems
- Weird Algorithm37367 / 38919
- Missing Number31589 / 33486
- Repetitions27811 / 29314
- Increasing Array25719 / 26815
- Permutations22929 / 23743
- Number Spiral16108 / 17559
- Two Knights11980 / 12389
- Two Sets12847 / 13991
- Bit Strings15404 / 16264
- Trailing Zeros14532 / 15491
- Coin Piles12638 / 13973
- Palindrome Reorder11209 / 12014
- Gray Code4939 / 5613
- Tower of Hanoi4502 / 4711
- Creating Strings10149 / 10442
- Apple Division9162 / 10651
- Chessboard and Queens5462 / 5560
- Digit Queries2499 / 3105
- Grid Paths2201 / 2897
Sorting and Searching
- Distinct Numbers16365 / 16950
- Apartments11253 / 12952
- Ferris Wheel10663 / 11805
- Concert Tickets8379 / 10267
- Restaurant Customers8561 / 9412
- Movie Festival8259 / 8775
- Sum of Two Values9664 / 10658
- Maximum Subarray Sum9614 / 10009
- Stick Lengths8420 / 8947
- Missing Coin Sum4130 / 4315
- Collecting Numbers4196 / 4592
- Collecting Numbers II1663 / 2193
- Playlist6797 / 7856
- Towers6824 / 7423
- Traffic Lights5222 / 5943
- Josephus Problem I2320 / 2697
- Josephus Problem II1414 / 1834
- Nested Ranges Check1094 / 1394
- Nested Ranges Count905 / 1008
- Room Allocation4041 / 4843
- Factory Machines4627 / 5060
- Tasks and Deadlines4579 / 4687
- Reading Books3818 / 4119
- Sum of Three Values5062 / 5668
- Sum of Four Values3513 / 3942
- Nearest Smaller Values4383 / 4586
- Subarray Sums I5174 / 5768
- Subarray Sums II4879 / 5460
- Subarray Divisibility4494 / 4829
- Subarray Distinct Values1706 / 1814
- Array Division3657 / 3886
- Sliding Median2825 / 3325
- Sliding Cost1979 / 2253
- Movie Festival II2301 / 2818
- Maximum Subarray Sum II2166 / 2595
Dynamic Programming
- Dice Combinations15087 / 16005
- Minimizing Coins13130 / 14020
- Coin Combinations I12201 / 13184
- Coin Combinations II10257 / 11696
- Removing Digits11519 / 11718
- Grid Paths10619 / 10961
- Book Shop9596 / 10589
- Array Description6663 / 7509
- Counting Towers2497 / 2669
- Edit Distance7127 / 7615
- Rectangle Cutting6097 / 6676
- Money Sums7068 / 7414
- Removal Game5149 / 5630
- Two Sets II5755 / 6265
- Increasing Subsequence5741 / 6616
- Projects3775 / 4291
- Elevator Rides1558 / 2126
- Counting Tilings881 / 986
- Counting Numbers1109 / 1250
Graph Algorithms
- Counting Rooms10242 / 10934
- Labyrinth6460 / 8001
- Building Roads8252 / 8633
- Message Route7140 / 7453
- Building Teams6862 / 7199
- Round Trip5541 / 6076
- Monsters3098 / 3931
- Shortest Routes I5668 / 6323
- Shortest Routes II4833 / 5231
- High Score2832 / 3931
- Flight Discount3245 / 3898
- Cycle Finding2701 / 3179
- Flight Routes2304 / 2545
- Round Trip II2674 / 3149
- Course Schedule3670 / 3829
- Longest Flight Route2400 / 3134
- Game Routes2713 / 3029
- Investigation1929 / 2095
- Planets Queries I1506 / 2031
- Planets Queries II780 / 952
- Planets Cycles1124 / 1257
- Road Reparation2389 / 2477
- Road Construction2444 / 2532
- Flight Routes Check2223 / 2446
- Planets and Kingdoms1885 / 1949
- Giant Pizza865 / 972
- Coin Collector1253 / 1380
- Mail Delivery1095 / 1229
- De Bruijn Sequence671 / 699
- Teleporters Path836 / 988
- Hamiltonian Flights987 / 1139
- Knight's Tour604 / 703
- Download Speed1035 / 1129
- Police Chase790 / 852
- School Dance816 / 849
- Distinct Routes500 / 706
Range Queries
- Static Range Sum Queries6746 / 7052
- Static Range Minimum Queries5156 / 5519
- Dynamic Range Sum Queries5149 / 5380
- Dynamic Range Minimum Queries4615 / 4740
- Range Xor Queries4774 / 4852
- Range Update Queries3715 / 3992
- Forest Queries3411 / 3542
- Hotel Queries2649 / 2830
- List Removals2241 / 2384
- Salary Queries1702 / 2027
- Prefix Sum Queries896 / 968
- Pizzeria Queries719 / 748
- Subarray Sum Queries1454 / 1611
- Distinct Values Queries1437 / 1677
- Increasing Array Queries368 / 433
- Forest Queries II1073 / 1141
- Range Updates and Sums1092 / 1321
- Polynomial Queries864 / 1016
- Range Queries and Copies579 / 606
Tree Algorithms
- Subordinates5444 / 5844
- Tree Matching2947 / 3571
- Tree Diameter4456 / 4744
- Tree Distances I3095 / 3397
- Tree Distances II2569 / 2679
- Company Queries I2766 / 2934
- Company Queries II2703 / 2822
- Distance Queries2643 / 2817
- Counting Paths1545 / 1645
- Subtree Queries1912 / 2046
- Path Queries1512 / 1587
- Path Queries II485 / 579
- Distinct Colors1386 / 1636
- Finding a Centroid828 / 858
- Fixed-Length Paths I424 / 473
- Fixed-Length Paths II327 / 358
Mathematics
- Josephus Queries498 / 642
- Exponentiation5305 / 5835
- Exponentiation II3711 / 4684
- Counting Divisors4185 / 4817
- Common Divisors2952 / 3423
- Sum of Divisors1680 / 2754
- Divisor Analysis663 / 922
- Prime Multiples694 / 857
- Counting Coprime Pairs457 / 564
- Binomial Coefficients2017 / 2301
- Creating Strings II1673 / 1821
- Distributing Apples1577 / 1701
- Christmas Party1415 / 1515
- Bracket Sequences I596 / 661
- Bracket Sequences II273 / 326
- Counting Necklaces301 / 325
- Counting Grids231 / 246
- Fibonacci Numbers1723 / 2205
- Throwing Dice1008 / 1100
- Graph Paths I871 / 935
- Graph Paths II730 / 757
- Dice Probability865 / 917
- Moving Robots465 / 493
- Candy Lottery636 / 653
- Inversion Probability557 / 568
- Stick Game834 / 854
- Nim Game I1023 / 1060
- Nim Game II836 / 870
- Stair Game568 / 644
- Grundy's Game232 / 295
- Another Game219 / 238
String Algorithms
- Word Combinations918 / 1464
- String Matching1981 / 2689
- Finding Borders1328 / 1516
- Finding Periods858 / 989
- Minimal Rotation606 / 906
- Longest Palindrome754 / 1050
- Required Substring350 / 606
- Palindrome Queries205 / 252
- Finding Patterns230 / 329
- Counting Patterns223 / 270
- Pattern Positions191 / 232
- Distinct Substrings209 / 250
- Repeating Substring195 / 213
- String Functions187 / 194
- Substring Order I145 / 155
- Substring Order II103 / 127
- Substring Distribution139 / 152
Geometry
- Point Location Test1015 / 1117
- Line Segment Intersection602 / 756
- Polygon Area695 / 721
- Point in Polygon382 / 482
- Polygon Lattice Points331 / 344
- Minimum Euclidean Distance284 / 390
- Convex Hull444 / 536
Advanced Techniques
- Meet in the Middle1046 / 1406
- Hamming Distance467 / 515
- Beautiful Subgrids279 / 338
- Reachable Nodes269 / 301
- Reachability Queries215 / 245
- Cut and Paste166 / 187
- Substring Reversals148 / 157
- Reversals and Sums146 / 151
- Necessary Roads225 / 228
- Necessary Cities196 / 208
- Eulerian Subgraphs111 / 116
- Monster Game I130 / 141
- Monster Game II128 / 134
- Subarray Squares143 / 168
- Houses and Schools102 / 112
- Knuth Division125 / 144
- Apples and Bananas120 / 131
- One Bit Positions115 / 131
- Signal Processing112 / 118
- New Roads Queries155 / 211
- Dynamic Connectivity95 / 104
- Parcel Delivery90 / 104
- Task Assignment90 / 95
- Distinct Routes II81 / 95
Additional Problems
- Shortest Subsequence880 / 1149
- Counting Bits938 / 1223
- Swap Game380 / 511
- Prüfer Code381 / 406
- Acyclic Graph Edges526 / 560
- Strongly Connected Edges181 / 196
- Even Outdegree Edges170 / 199
- Multiplication Table413 / 450
- Advertisement684 / 722
- Special Substrings136 / 147
- Permutation Inversions149 / 170
- Maximum Xor Subarray515 / 558
- Movie Festival Queries244 / 281
- Chess Tournament294 / 339
- Tree Traversals288 / 298
- Network Renovation214 / 311
- Graph Girth534 / 605
- Intersection Points354 / 385
- Inverse Inversions151 / 156
- Monotone Subsequences96 / 109
- String Reorder201 / 221
- Stack Weights83 / 95
- Pyramid Array200 / 239
- Increasing Subsequence II460 / 496
- String Removals254 / 286
- Bit Inversions504 / 555
- Xor Pyramid206 / 260
- Writing Numbers239 / 261
- String Transform155 / 183
- Letter Pair Move Game30 / 41
- Maximum Building I439 / 453
- Sorting Methods239 / 254
- Cyclic Array167 / 218
- List of Sums82 / 113
- Increasing Array II104 / 118
- Food Division155 / 186
- Bit Problem268 / 291
- Swap Round Sorting105 / 138
- Binary Subsequences33 / 59
- Tree Isomorphism I205 / 261
- Counting Sequences98 / 105
- Critical Cities100 / 152
- School Excursion272 / 290
- Coin Grid160 / 195
- Robot Path79 / 145
- Programmers and Artists52 / 67
- Course Schedule II318 / 461
- Removing Digits II36 / 60
- Coin Arrangement36 / 51
- Counting Bishops52 / 58
- Grid Puzzle I78 / 89
- Grid Puzzle II55 / 60
- Empty String278 / 349
- Grid Paths211 / 269
- Bit Substrings61 / 70
- Reversal Sorting51 / 66
- Counting Reorders36 / 50
- Book Shop II234 / 260
- Network Breakdown227 / 237
- Visiting Cities174 / 231
- Missing Coin Sum Queries41 / 65
- Number Grid271 / 330
- Maximum Building II120 / 146
- Filling Trominos39 / 58
- Stick Divisions562 / 669
- Coding Company250 / 313
- Flight Route Requests134 / 149
- Two Stacks Sorting21 / 74
- Tree Isomorphism II180 / 204
- Forbidden Cities145 / 180
- Area of Rectangles217 / 252
- Grid Completion23 / 33
- Creating Offices87 / 125
- Permutations II238 / 266
- Functional Graph Distribution29 / 35
- New Flight Routes104 / 213
- Grid Path Construction20 / 32