General
Introductory Problems
- Weird Algorithm177349 / 185234
- Missing Number152997 / 159912
- Repetitions132979 / 137966
- Increasing Array125351 / 129492
- Permutations109802 / 112962
- Number Spiral78067 / 84625
- Two Knights60232 / 62000
- Two Sets65482 / 70038
- Bit Strings74445 / 78336
- Trailing Zeros68926 / 73087
- Coin Piles61328 / 66698
- Palindrome Reorder56994 / 59949
- Gray Code38971 / 43450
- Tower of Hanoi36334 / 37716
- Creating Strings48085 / 49244
- Apple Division48817 / 54682
- Chessboard and Queens29736 / 30236
- Raab Game I7827 / 8763
- Mex Grid Construction7593 / 7957
- Knight Moves Grid7668 / 7835
- Grid Coloring I6450 / 6675
- Digit Queries20877 / 23904
- String Reorder5758 / 6570
- Grid Path Description11706 / 14978
Sorting and Searching
- Distinct Numbers88254 / 94936
- Apartments66317 / 72898
- Ferris Wheel63942 / 68482
- Concert Tickets51310 / 59133
- Restaurant Customers52154 / 55970
- Movie Festival50727 / 53459
- Sum of Two Values58607 / 65100
- Maximum Subarray Sum55916 / 58193
- Stick Lengths50103 / 52230
- Missing Coin Sum38398 / 39697
- Collecting Numbers39315 / 41839
- Collecting Numbers II17323 / 21530
- Playlist39250 / 44406
- Towers39212 / 41812
- Traffic Lights30539 / 33927
- Distinct Values Subarrays10642 / 11883
- Distinct Values Subsequences8207 / 8920
- Josephus Problem I23812 / 26005
- Josephus Problem II12970 / 17743
- Nested Ranges Check14217 / 16053
- Nested Ranges Count9513 / 11105
- Room Allocation23185 / 26357
- Factory Machines33599 / 36251
- Tasks and Deadlines26802 / 27319
- Reading Books21780 / 23223
- Sum of Three Values31280 / 34349
- Sum of Four Values19551 / 21563
- Nearest Smaller Values26222 / 27059
- Subarray Sums I34784 / 36855
- Subarray Sums II31742 / 37169
- Subarray Divisibility28724 / 31063
- Distinct Values Subarrays II17577 / 19094
- Array Division27215 / 28520
- Movie Festival II14817 / 17632
- Maximum Subarray Sum II13820 / 16263
Dynamic Programming
- Dice Combinations92787 / 97896
- Minimizing Coins80255 / 85887
- Coin Combinations I73335 / 78977
- Coin Combinations II62224 / 69864
- Removing Digits69189 / 70551
- Grid Paths I64946 / 66661
- Book Shop58588 / 64004
- Array Description43465 / 47881
- Counting Towers27124 / 28620
- Edit Distance43223 / 45449
- Longest Common Subsequence15269 / 15770
- Rectangle Cutting35709 / 38772
- Minimal Grid Path7148 / 11779
- Money Sums42092 / 43570
- Removal Game26196 / 33711
- Two Sets II33272 / 35564
- Mountain Range4948 / 8414
- Increasing Subsequence33757 / 37687
- Projects23786 / 26345
- Elevator Rides15634 / 19324
- Counting Tilings9159 / 9895
- Counting Numbers13698 / 15145
- Increasing Subsequence II6198 / 7266
Graph Algorithms
- Counting Rooms64522 / 67514
- Labyrinth45922 / 53896
- Building Roads56538 / 58410
- Message Route49048 / 50815
- Building Teams46271 / 48497
- Round Trip36712 / 39672
- Monsters26119 / 30135
- Shortest Routes I40520 / 44159
- Shortest Routes II32755 / 36347
- High Score21069 / 28346
- Flight Discount27000 / 30971
- Cycle Finding19040 / 22721
- Flight Routes18572 / 20481
- Round Trip II20584 / 22830
- Course Schedule27160 / 28473
- Longest Flight Route19939 / 23948
- Game Routes21723 / 23045
- Investigation16515 / 17606
- Planets Queries I14319 / 16501
- Planets Queries II5201 / 6452
- Planets Cycles8641 / 9539
- Road Reparation21210 / 22026
- Road Construction23094 / 23783
- Flight Routes Check18345 / 19712
- Planets and Kingdoms14958 / 15568
- Giant Pizza6307 / 6879
- Coin Collector9940 / 10864
- Mail Delivery7904 / 8577
- De Bruijn Sequence4162 / 4350
- Teleporters Path6137 / 6892
- Hamiltonian Flights9380 / 10599
- Knight's Tour3502 / 4184
- Download Speed6085 / 7909
- Police Chase4862 / 5392
- School Dance5337 / 5623
- Distinct Routes3766 / 4817
Range Queries
- Static Range Sum Queries45167 / 47141
- Static Range Minimum Queries31045 / 33214
- Dynamic Range Sum Queries32294 / 33663
- Dynamic Range Minimum Queries29160 / 29834
- Range Xor Queries29776 / 30164
- Range Update Queries24105 / 25728
- Forest Queries24731 / 25569
- Hotel Queries17568 / 18533
- List Removals14613 / 15297
- Salary Queries11314 / 13969
- Prefix Sum Queries9480 / 10179
- Pizzeria Queries7565 / 7819
- Visible Buildings Queries2331 / 2529
- Range Interval Queries1777 / 2360
- Subarray Sum Queries8720 / 9401
- Subarray Sum Queries II2634 / 2713
- Distinct Values Queries8274 / 10007
- Distinct Values Queries II1472 / 1668
- Increasing Array Queries3145 / 3574
- Movie Festival Queries1757 / 1930
- Forest Queries II5133 / 5488
- Range Updates and Sums7234 / 8451
- Polynomial Queries5305 / 6177
- Range Queries and Copies3738 / 3980
- Missing Coin Sum Queries891 / 1217
Tree Algorithms
- Subordinates37140 / 39621
- Tree Matching21531 / 24764
- Tree Diameter30409 / 32083
- Tree Distances I23645 / 25254
- Tree Distances II19262 / 20104
- Company Queries I21659 / 22709
- Company Queries II20260 / 21253
- Distance Queries18270 / 19495
- Counting Paths11559 / 12181
- Subtree Queries13559 / 14395
- Path Queries10939 / 11528
- Path Queries II4597 / 6712
- Distinct Colors10478 / 11448
- Finding a Centroid8522 / 8852
- Fixed-Length Paths I4271 / 5348
- Fixed-Length Paths II2098 / 3622
Mathematics
- Josephus Queries5909 / 7354
- Exponentiation28719 / 30541
- Exponentiation II20043 / 23751
- Counting Divisors26403 / 29698
- Common Divisors16970 / 19544
- Sum of Divisors9692 / 14119
- Divisor Analysis6644 / 8761
- Prime Multiples7720 / 8914
- Counting Coprime Pairs5106 / 5874
- Next Prime2743 / 3119
- Binomial Coefficients12367 / 13628
- Creating Strings II10227 / 10762
- Distributing Apples9768 / 10475
- Christmas Party8148 / 8676
- Permutation Order1318 / 1353
- Permutation Rounds1921 / 2113
- Bracket Sequences I5444 / 5899
- Bracket Sequences II2908 / 3300
- Counting Necklaces2630 / 2839
- Counting Grids2215 / 2349
- Fibonacci Numbers8074 / 10029
- Throwing Dice4267 / 4615
- Graph Paths I4141 / 4409
- Graph Paths II3473 / 3634
- System of Linear Equations668 / 722
- Sum of Four Squares945 / 1131
- Triangle Number Sums828 / 990
- Dice Probability3658 / 3926
- Moving Robots1897 / 1998
- Candy Lottery1988 / 3651
- Inversion Probability597 / 2691
- Stick Game4171 / 4268
- Nim Game I5575 / 5777
- Nim Game II4410 / 4579
- Stair Game2989 / 3236
- Grundy's Game2089 / 2733
- Another Game2365 / 2539
String Algorithms
- Word Combinations7217 / 10190
- String Matching13686 / 18032
- Finding Borders10094 / 10971
- Finding Periods7224 / 8119
- Minimal Rotation3608 / 5253
- Longest Palindrome5313 / 6874
- All Palindromes985 / 1099
- Required Substring2026 / 2996
- Palindrome Queries2479 / 2857
- Finding Patterns2354 / 3247
- Counting Patterns2236 / 2717
- Pattern Positions1888 / 2262
- Distinct Substrings2111 / 2494
- Distinct Subsequences1362 / 1439
- Repeating Substring2279 / 2608
- String Functions2001 / 2095
- Inverse Suffix Array389 / 443
- String Transform692 / 817
- Substring Order I1439 / 1587
- Substring Order II982 / 1250
- Substring Distribution1344 / 1452
Geometry
- Point Location Test8629 / 9565
- Line Segment Intersection5112 / 6343
- Polygon Area5863 / 6181
- Point in Polygon3293 / 4129
- Polygon Lattice Points2672 / 2855
- Minimum Euclidean Distance2369 / 3300
- Convex Hull3924 / 4643
- Maximum Manhattan Distances862 / 895
- All Manhattan Distances897 / 984
- Intersection Points2347 / 2526
- Line Segments Trace I474 / 489
- Line Segments Trace II395 / 414
- Lines and Queries I518 / 543
- Lines and Queries II462 / 483
- Area of Rectangles1379 / 1531
- Robot Path378 / 688
Advanced Techniques
- Meet in the Middle8356 / 11197
- Hamming Distance3682 / 4019
- Corner Subgrid Check332 / 706
- Corner Subgrid Count2507 / 2849
- Reachable Nodes2616 / 2800
- Reachability Queries1759 / 2056
- Cut and Paste1808 / 1994
- Substring Reversals1598 / 1723
- Reversals and Sums1623 / 1732
- Necessary Roads2336 / 2395
- Necessary Cities2168 / 2263
- Eulerian Subgraphs926 / 975
- Monster Game I1388 / 1537
- Monster Game II1225 / 1307
- Subarray Squares1735 / 2008
- Houses and Schools947 / 1117
- Knuth Division1129 / 1264
- Apples and Bananas1323 / 1429
- One Bit Positions1000 / 1087
- Signal Processing984 / 1050
- New Roads Queries2633 / 3155
- Dynamic Connectivity1210 / 1352
- Parcel Delivery953 / 1039
- Task Assignment1099 / 1185
- Distinct Routes II727 / 818
Sliding Window Problems
- Sliding Window Sum8076 / 8336
- Sliding Window Minimum6074 / 6906
- Sliding Window Xor5937 / 6013
- Sliding Window Or2672 / 4415
- Sliding Window Distinct Values4246 / 4941
- Sliding Window Mode3304 / 3497
- Sliding Window Mex3116 / 3277
- Sliding Window Median15310 / 17390
- Sliding Window Cost9996 / 11481
- Sliding Window Inversions1669 / 1764
- Sliding Window Advertisement322 / 505
Interactive Problems
- Hidden Integer2908 / 3030
- Hidden Permutation1309 / 1513
- K-th Highest Score595 / 718
- Permuted Binary Strings700 / 719
- Colored Chairs658 / 697
- Inversion Sorting383 / 431
Bitwise Operations
- Counting Bits6262 / 8029
- Maximum Xor Subarray3700 / 4225
- Maximum Xor Subset1397 / 1533
- Number of Subset Xors1215 / 1242
- K Subset Xors634 / 743
- All Subarray Xors383 / 590
- Xor Pyramid Peak2461 / 2943
- Xor Pyramid Diagonal438 / 490
- Xor Pyramid Row377 / 441
- SOS Bit Problem2595 / 2748
- And Subset Count621 / 645
Construction Problems
- Inverse Inversions2078 / 2218
- Monotone Subsequences1257 / 1484
- Third Permutation559 / 687
- Permutation Prime Sums561 / 603
- Chess Tournament1391 / 1604
- Distinct Sums Grid200 / 298
- Filling Trominos309 / 531
- Grid Path Construction170 / 500
Advanced Graph Problems
- Nearest Shops964 / 1237
- Prüfer Code1731 / 1853
- Tree Traversals1423 / 1556
- Course Schedule II2361 / 3301
- Acyclic Graph Edges2461 / 2609
- Strongly Connected Edges1805 / 2093
- Even Outdegree Edges1585 / 1840
- Graph Girth3992 / 4496
- Fixed Length Walk Queries479 / 530
- Transfer Speeds Sum539 / 556
- MST Edge Check886 / 956
- MST Edge Set Check331 / 373
- MST Edge Cost522 / 543
- Network Breakdown1344 / 1459
- Tree Coin Collecting I457 / 496
- Tree Coin Collecting II260 / 297
- Tree Isomorphism I1231 / 1454
- Tree Isomorphism II1023 / 1169
- Flight Route Requests582 / 720
- Critical Cities507 / 756
- Visiting Cities770 / 1005
- Graph Coloring297 / 346
- Bus Companies345 / 355
- Split into Two Paths141 / 239
- Network Renovation1040 / 1363
- Forbidden Cities987 / 1271
- Creating Offices477 / 619
- New Flight Routes411 / 1041
Counting Problems
- Filled Subgrid Count I792 / 882
- Filled Subgrid Count II423 / 523
- All Letter Subgrid Count I241 / 345
- All Letter Subgrid Count II152 / 229
- Border Subgrid Count I129 / 219
- Border Subgrid Count II144 / 166
- Raab Game II145 / 165
- Empty String1926 / 2334
- Permutation Inversions1142 / 1257
- Counting Bishops447 / 500
- Counting Sequences767 / 822
- Grid Paths II854 / 1074
- Counting Permutations988 / 1113
- Grid Completion263 / 332
- Counting Reorders300 / 415
- Tournament Graph Distribution147 / 157
- Collecting Numbers Distribution155 / 162
- Functional Graph Distribution281 / 344
Additional Problems I
- Shortest Subsequence3277 / 4277
- Distinct Values Sum871 / 895
- Distinct Values Splits616 / 659
- Swap Game2264 / 2890
- Beautiful Permutation II766 / 1173
- Multiplication Table7832 / 8684
- Bubble Sort Rounds I554 / 629
- Bubble Sort Rounds II386 / 429
- Nearest Campsites I241 / 282
- Nearest Campsites II233 / 251
- Advertisement4925 / 5205
- Special Substrings1089 / 1192
- Counting LCM Arrays375 / 407
- Square Subsets288 / 317
- Subarray Sum Constraints587 / 627
- Water Containers Moves233 / 247
- Water Containers Queries268 / 283
- Stack Weights653 / 780
- Maximum Average Subarrays228 / 251
- Subsets with Fixed Average272 / 295
- Two Array Average277 / 308
- Pyramid Array868 / 1045
- Permutation Subsequence319 / 330
- Bit Inversions2581 / 2900
- Writing Numbers815 / 882
- Letter Pair Move Game235 / 325
- Maximum Building I2283 / 2383
- Sorting Methods849 / 906
- Cyclic Array1376 / 1551
- List of Sums545 / 704
Additional Problems II
- Bouncing Ball Steps318 / 350
- Bouncing Ball Cycle134 / 181
- Knight Moves Queries166 / 199
- K Subset Sums I261 / 325
- K Subset Sums II155 / 194
- Increasing Array II914 / 1042
- Food Division580 / 690
- Swap Round Sorting451 / 558
- Binary Subsequences321 / 462
- School Excursion1538 / 1624
- Coin Grid1030 / 1195
- Grid Coloring II173 / 222
- Programmers and Artists565 / 782
- Removing Digits II245 / 519
- Coin Arrangement373 / 493
- Replace with Difference176 / 209
- Grid Puzzle I608 / 666
- Grid Puzzle II592 / 647
- Bit Substrings449 / 541
- Reversal Sorting396 / 476
- Book Shop II1435 / 1634
- GCD Subsets513 / 529
- Minimum Cost Pairs182 / 228
- Same Sum Subsets158 / 300
- Mex Grid Queries931 / 1086
- Maximum Building II492 / 604
- Stick Divisions4164 / 4850
- Stick Difference105 / 337
- Coding Company1666 / 2174
- Two Stacks Sorting210 / 643