General
Introductory Problems
- Weird Algorithm98459 / 103131
- Missing Number83773 / 88379
- Repetitions73136 / 76629
- Increasing Array68274 / 71162
- Permutations60040 / 62099
- Number Spiral42479 / 46333
- Two Knights31867 / 33016
- Two Sets34431 / 37439
- Bit Strings40117 / 42370
- Trailing Zeros37574 / 40187
- Coin Piles33068 / 36494
- Palindrome Reorder30205 / 32208
- Gray Code18777 / 21468
- Tower of Hanoi17512 / 18264
- Creating Strings26048 / 26844
- Apple Division25259 / 29003
- Chessboard and Queens15012 / 15328
- Digit Queries10116 / 12174
- Grid Paths6249 / 7987
Sorting and Searching
- Distinct Numbers46061 / 50529
- Apartments33580 / 38173
- Ferris Wheel31943 / 34954
- Concert Tickets25557 / 30449
- Restaurant Customers26266 / 28679
- Movie Festival24706 / 26430
- Sum of Two Values29124 / 33249
- Maximum Subarray Sum28745 / 30248
- Stick Lengths25450 / 26893
- Missing Coin Sum17751 / 18478
- Collecting Numbers18404 / 19936
- Collecting Numbers II7327 / 9596
- Playlist19148 / 22341
- Towers19640 / 21247
- Traffic Lights15386 / 17347
- Josephus Problem I10442 / 11847
- Josephus Problem II6052 / 7898
- Nested Ranges Check5939 / 6986
- Nested Ranges Count4238 / 4890
- Room Allocation11183 / 13033
- Factory Machines14364 / 16114
- Tasks and Deadlines12997 / 13312
- Reading Books10368 / 11142
- Sum of Three Values15114 / 17139
- Sum of Four Values9579 / 10844
- Nearest Smaller Values12802 / 13311
- Subarray Sums I16497 / 17776
- Subarray Sums II15264 / 17447
- Subarray Divisibility13401 / 14795
- Subarray Distinct Values7600 / 8237
- Array Division12234 / 12987
- Sliding Window Median8083 / 9240
- Sliding Window Cost5652 / 6515
- Movie Festival II6978 / 8471
- Maximum Subarray Sum II6385 / 7668
Dynamic Programming
- Dice Combinations45440 / 48436
- Minimizing Coins39109 / 42357
- Coin Combinations I35986 / 39271
- Coin Combinations II30195 / 34687
- Removing Digits33399 / 34262
- Grid Paths31763 / 32834
- Book Shop27909 / 31233
- Array Description20166 / 22770
- Counting Towers11458 / 12164
- Edit Distance20930 / 22263
- Rectangle Cutting17473 / 19169
- Money Sums20835 / 21767
- Removal Game14889 / 16577
- Two Sets II16428 / 17946
- Increasing Subsequence16904 / 19213
- Projects11377 / 12929
- Elevator Rides6837 / 8805
- Counting Tilings3906 / 4302
- Counting Numbers5272 / 6022
Graph Algorithms
- Counting Rooms31032 / 33043
- Labyrinth20357 / 25299
- Building Roads26860 / 28008
- Message Route22817 / 23937
- Building Teams21902 / 23020
- Round Trip17010 / 18794
- Monsters10691 / 13180
- Shortest Routes I18270 / 20772
- Shortest Routes II15400 / 16885
- High Score7694 / 12682
- Flight Discount10738 / 13175
- Cycle Finding7981 / 10070
- Flight Routes7433 / 8385
- Round Trip II8919 / 10264
- Course Schedule12381 / 12933
- Longest Flight Route7639 / 10278
- Game Routes8955 / 9876
- Investigation6548 / 7124
- Planets Queries I5543 / 6783
- Planets Queries II2220 / 2760
- Planets Cycles3701 / 4167
- Road Reparation8856 / 9313
- Road Construction9341 / 9713
- Flight Routes Check7951 / 8791
- Planets and Kingdoms6410 / 6691
- Giant Pizza2579 / 2907
- Coin Collector3987 / 4530
- Mail Delivery3459 / 3853
- De Bruijn Sequence1859 / 1960
- Teleporters Path2739 / 3073
- Hamiltonian Flights3833 / 4372
- Knight's Tour1619 / 1920
- Download Speed2656 / 3784
- Police Chase2169 / 2492
- School Dance2391 / 2551
- Distinct Routes1530 / 2095
Range Queries
- Static Range Sum Queries21113 / 22108
- Static Range Minimum Queries15700 / 16820
- Dynamic Range Sum Queries16170 / 16929
- Dynamic Range Minimum Queries14714 / 15108
- Range Xor Queries14882 / 15109
- Range Update Queries11849 / 12783
- Forest Queries11630 / 12114
- Hotel Queries8489 / 8974
- List Removals7061 / 7463
- Salary Queries5212 / 6320
- Prefix Sum Queries4206 / 4607
- Pizzeria Queries3425 / 3555
- Subarray Sum Queries4373 / 4905
- Distinct Values Queries4096 / 4998
- Increasing Array Queries1485 / 1710
- Forest Queries II2825 / 3062
- Range Updates and Sums3384 / 4139
- Polynomial Queries2596 / 3051
- Range Queries and Copies1824 / 1979
Tree Algorithms
- Subordinates17480 / 18921
- Tree Matching9795 / 11559
- Tree Diameter14495 / 15546
- Tree Distances I10747 / 11668
- Tree Distances II8798 / 9195
- Company Queries I9712 / 10295
- Company Queries II9115 / 9637
- Distance Queries8514 / 9145
- Counting Paths5082 / 5449
- Subtree Queries6250 / 6700
- Path Queries4995 / 5281
- Path Queries II1741 / 2922
- Distinct Colors4755 / 5365
- Finding a Centroid3887 / 4069
- Fixed-Length Paths I1593 / 2304
- Fixed-Length Paths II657 / 1573
Mathematics
- Josephus Queries2536 / 3209
- Exponentiation14759 / 15956
- Exponentiation II10541 / 12998
- Counting Divisors12691 / 14547
- Common Divisors8520 / 10233
- Sum of Divisors4863 / 7457
- Divisor Analysis3151 / 4213
- Prime Multiples3425 / 4064
- Counting Coprime Pairs2162 / 2560
- Binomial Coefficients5958 / 6756
- Creating Strings II4997 / 5353
- Distributing Apples4885 / 5295
- Christmas Party3782 / 4115
- Bracket Sequences I2566 / 2847
- Bracket Sequences II1318 / 1524
- Counting Necklaces1279 / 1391
- Counting Grids1028 / 1100
- Fibonacci Numbers4358 / 5611
- Throwing Dice2357 / 2566
- Graph Paths I2154 / 2323
- Graph Paths II1808 / 1893
- Dice Probability2058 / 2187
- Moving Robots1034 / 1104
- Candy Lottery1587 / 1632
- Inversion Probability459 / 1423
- Stick Game2113 / 2173
- Nim Game I2658 / 2769
- Nim Game II2158 / 2254
- Stair Game1499 / 1645
- Grundy's Game958 / 1240
- Another Game1097 / 1195
String Algorithms
- Word Combinations3109 / 4770
- String Matching6205 / 8953
- Finding Borders4609 / 5167
- Finding Periods3145 / 3578
- Minimal Rotation1571 / 2575
- Longest Palindrome2368 / 3324
- Required Substring921 / 1505
- Palindrome Queries1142 / 1368
- Finding Patterns984 / 1457
- Counting Patterns887 / 1177
- Pattern Positions786 / 1007
- Distinct Substrings938 / 1131
- Repeating Substring956 / 1077
- String Functions908 / 959
- Substring Order I673 / 723
- Substring Order II442 / 561
- Substring Distribution612 / 670
Geometry
- Point Location Test4130 / 4768
- Line Segment Intersection2505 / 3276
- Polygon Area3005 / 3234
- Point in Polygon1652 / 2108
- Polygon Lattice Points1410 / 1465
- Minimum Euclidean Distance1285 / 1769
- Convex Hull2069 / 2521
Advanced Techniques
- Meet in the Middle3571 / 5525
- Hamming Distance1968 / 2132
- Beautiful Subgrids1387 / 1561
- Reachable Nodes1397 / 1517
- Reachability Queries963 / 1143
- Cut and Paste906 / 1021
- Substring Reversals792 / 870
- Reversals and Sums792 / 865
- Necessary Roads1201 / 1237
- Necessary Cities1121 / 1179
- Eulerian Subgraphs504 / 533
- Monster Game I729 / 803
- Monster Game II652 / 707
- Subarray Squares723 / 853
- Houses and Schools474 / 546
- Knuth Division553 / 626
- Apples and Bananas515 / 572
- One Bit Positions489 / 544
- Signal Processing457 / 500
- New Roads Queries1200 / 1463
- Dynamic Connectivity545 / 621
- Parcel Delivery438 / 499
- Task Assignment416 / 452
- Distinct Routes II349 / 407
Additional Problems
- Shortest Subsequence1976 / 2542
- Counting Bits2269 / 2938
- Swap Game1230 / 1585
- Prüfer Code874 / 969
- Acyclic Graph Edges1359 / 1450
- Strongly Connected Edges849 / 935
- Even Outdegree Edges772 / 902
- Multiplication Table2924 / 3339
- Advertisement2529 / 2698
- Special Substrings577 / 625
- Permutation Inversions622 / 688
- Maximum Xor Subarray1452 / 1589
- Movie Festival Queries643 / 719
- Chess Tournament723 / 827
- Tree Traversals696 / 782
- Network Renovation614 / 815
- Graph Girth1880 / 2190
- Intersection Points1143 / 1229
- Inverse Inversions631 / 662
- Monotone Subsequences427 / 474
- String Reorder506 / 559
- Stack Weights369 / 430
- Pyramid Array497 / 591
- Increasing Subsequence II1453 / 1575
- String Removals633 / 688
- Bit Inversions1471 / 1719
- Xor Pyramid776 / 987
- Writing Numbers508 / 549
- String Transform326 / 405
- Letter Pair Move Game114 / 170
- Maximum Building I1326 / 1390
- Sorting Methods529 / 566
- Cyclic Array658 / 758
- List of Sums299 / 401
- Increasing Array II496 / 565
- Food Division365 / 432
- Bit Problem957 / 1033
- Swap Round Sorting282 / 351
- Binary Subsequences148 / 235
- Tree Isomorphism I660 / 767
- Counting Sequences379 / 409
- Critical Cities251 / 397
- School Excursion855 / 913
- Coin Grid465 / 554
- Robot Path197 / 340
- Programmers and Artists313 / 402
- Course Schedule II1022 / 1454
- Removing Digits II127 / 269
- Coin Arrangement214 / 282
- Counting Bishops225 / 253
- Grid Puzzle I327 / 357
- Grid Puzzle II241 / 270
- Empty String918 / 1105
- Grid Paths501 / 622
- Bit Substrings224 / 280
- Reversal Sorting215 / 261
- Counting Reorders131 / 198
- Book Shop II650 / 739
- Network Breakdown613 / 653
- Visiting Cities452 / 587
- Missing Coin Sum Queries250 / 331
- Number Grid589 / 705
- Maximum Building II292 / 359
- Filling Trominos125 / 212
- Stick Divisions2339 / 2778
- Coding Company885 / 1130
- Flight Route Requests285 / 347
- Two Stacks Sorting94 / 324
- Tree Isomorphism II543 / 632
- Forbidden Cities453 / 593
- Area of Rectangles682 / 770
- Grid Completion132 / 174
- Creating Offices256 / 334
- Permutations II573 / 656
- Functional Graph Distribution146 / 183
- New Flight Routes202 / 485
- Grid Path Construction65 / 235