General
Introductory Problems
- Weird Algorithm172044 / 179795
- Missing Number148579 / 155355
- Repetitions129180 / 134089
- Increasing Array121764 / 125853
- Permutations106795 / 109892
- Number Spiral75753 / 82201
- Two Knights58399 / 60138
- Two Sets63456 / 67956
- Bit Strings72290 / 76131
- Trailing Zeros67008 / 71116
- Coin Piles59564 / 64858
- Palindrome Reorder55363 / 58287
- Gray Code37738 / 42109
- Tower of Hanoi35156 / 36503
- Creating Strings46692 / 47833
- Apple Division47345 / 53125
- Chessboard and Queens28814 / 29298
- Raab Game I7093 / 7990
- Mex Grid Construction6911 / 7249
- Knight Moves Grid6983 / 7139
- Grid Coloring I5876 / 6084
- Digit Queries20244 / 23253
- String Reorder5271 / 6031
- Grid Path Description11330 / 14541
Sorting and Searching
- Distinct Numbers85407 / 91972
- Apartments64105 / 70596
- Ferris Wheel61679 / 66130
- Concert Tickets49502 / 57169
- Restaurant Customers50353 / 54103
- Movie Festival48912 / 51607
- Sum of Two Values56702 / 63056
- Maximum Subarray Sum54193 / 56445
- Stick Lengths48560 / 50650
- Missing Coin Sum37062 / 38343
- Collecting Numbers37925 / 40420
- Collecting Numbers II16568 / 20705
- Playlist37906 / 42983
- Towers37934 / 40485
- Traffic Lights29495 / 32818
- Distinct Values Subarrays9594 / 10806
- Distinct Values Subsequences7378 / 8053
- Josephus Problem I22875 / 25020
- Josephus Problem II12500 / 17101
- Nested Ranges Check13604 / 15426
- Nested Ranges Count9112 / 10666
- Room Allocation22298 / 25406
- Factory Machines32250 / 34882
- Tasks and Deadlines25812 / 26323
- Reading Books20919 / 22335
- Sum of Three Values30282 / 33314
- Sum of Four Values18893 / 20867
- Nearest Smaller Values25297 / 26122
- Subarray Sums I33535 / 35600
- Subarray Sums II30585 / 35902
- Subarray Divisibility27702 / 29997
- Distinct Values Subarrays II16913 / 18414
- Array Division26218 / 27495
- Movie Festival II14211 / 16966
- Maximum Subarray Sum II13244 / 15631
Dynamic Programming
- Dice Combinations89465 / 94432
- Minimizing Coins77421 / 82882
- Coin Combinations I70812 / 76338
- Coin Combinations II60035 / 67479
- Removing Digits66650 / 67947
- Grid Paths I62664 / 64342
- Book Shop56476 / 61752
- Array Description41766 / 46088
- Counting Towers25858 / 27327
- Edit Distance41671 / 43852
- Longest Common Subsequence13711 / 14178
- Rectangle Cutting34390 / 37396
- Minimal Grid Path6286 / 10599
- Money Sums40602 / 42053
- Removal Game24890 / 32369
- Two Sets II31953 / 34226
- Mountain Range4336 / 7498
- Increasing Subsequence32538 / 36375
- Projects22768 / 25275
- Elevator Rides14805 / 18391
- Counting Tilings8698 / 9415
- Counting Numbers12920 / 14336
- Increasing Subsequence II5730 / 6696
Graph Algorithms
- Counting Rooms62082 / 65014
- Labyrinth43892 / 51774
- Building Roads54353 / 56198
- Message Route47047 / 48786
- Building Teams44447 / 46657
- Round Trip35202 / 38113
- Monsters24798 / 28757
- Shortest Routes I38831 / 42441
- Shortest Routes II31403 / 34951
- High Score19971 / 27158
- Flight Discount25551 / 29481
- Cycle Finding18028 / 21682
- Flight Routes17600 / 19470
- Round Trip II19588 / 21806
- Course Schedule25964 / 27273
- Longest Flight Route18890 / 22866
- Game Routes20655 / 21955
- Investigation15546 / 16608
- Planets Queries I13503 / 15632
- Planets Queries II4914 / 6130
- Planets Cycles8206 / 9086
- Road Reparation20188 / 20985
- Road Construction22045 / 22720
- Flight Routes Check17516 / 18864
- Planets and Kingdoms14233 / 14839
- Giant Pizza6016 / 6568
- Coin Collector9419 / 10320
- Mail Delivery7557 / 8221
- De Bruijn Sequence4005 / 4185
- Teleporters Path5840 / 6591
- Hamiltonian Flights8897 / 10065
- Knight's Tour3360 / 4028
- Download Speed5837 / 7634
- Police Chase4631 / 5153
- School Dance5093 / 5371
- Distinct Routes3614 / 4648
Range Queries
- Static Range Sum Queries43348 / 45252
- Static Range Minimum Queries29834 / 31902
- Dynamic Range Sum Queries31049 / 32381
- Dynamic Range Minimum Queries28081 / 28742
- Range Xor Queries28804 / 29185
- Range Update Queries23142 / 24736
- Forest Queries23843 / 24668
- Hotel Queries16852 / 17802
- List Removals13990 / 14665
- Salary Queries10760 / 13350
- Prefix Sum Queries9049 / 9729
- Pizzeria Queries7266 / 7518
- Visible Buildings Queries2126 / 2310
- Range Interval Queries1617 / 2163
- Subarray Sum Queries8394 / 9063
- Subarray Sum Queries II2376 / 2450
- Distinct Values Queries7944 / 9650
- Distinct Values Queries II1344 / 1528
- Increasing Array Queries3043 / 3468
- Movie Festival Queries1678 / 1849
- Forest Queries II4984 / 5336
- Range Updates and Sums6926 / 8122
- Polynomial Queries5109 / 5975
- Range Queries and Copies3620 / 3858
- Missing Coin Sum Queries830 / 1148
Tree Algorithms
- Subordinates35701 / 38121
- Tree Matching20539 / 23685
- Tree Diameter29166 / 30815
- Tree Distances I22547 / 24133
- Tree Distances II18378 / 19193
- Company Queries I20624 / 21647
- Company Queries II19275 / 20248
- Distance Queries17409 / 18605
- Counting Paths10975 / 11587
- Subtree Queries12966 / 13773
- Path Queries10448 / 11021
- Path Queries II4396 / 6454
- Distinct Colors10061 / 11012
- Finding a Centroid8182 / 8505
- Fixed-Length Paths I4078 / 5136
- Fixed-Length Paths II1971 / 3454
Mathematics
- Josephus Queries5651 / 7062
- Exponentiation27841 / 29628
- Exponentiation II19439 / 23090
- Counting Divisors25504 / 28711
- Common Divisors16414 / 18944
- Sum of Divisors9321 / 13691
- Divisor Analysis6410 / 8496
- Prime Multiples7439 / 8609
- Counting Coprime Pairs4945 / 5700
- Next Prime2521 / 2875
- Binomial Coefficients11922 / 13164
- Creating Strings II9872 / 10391
- Distributing Apples9407 / 10087
- Christmas Party7833 / 8356
- Permutation Order1208 / 1243
- Permutation Rounds1734 / 1920
- Bracket Sequences I5234 / 5680
- Bracket Sequences II2766 / 3151
- Counting Necklaces2538 / 2741
- Counting Grids2125 / 2256
- Fibonacci Numbers7851 / 9771
- Throwing Dice4136 / 4480
- Graph Paths I4013 / 4277
- Graph Paths II3354 / 3510
- System of Linear Equations606 / 660
- Sum of Four Squares900 / 1044
- Triangle Number Sums758 / 911
- Dice Probability3509 / 3768
- Moving Robots1822 / 1921
- Candy Lottery1841 / 3476
- Inversion Probability547 / 2591
- Stick Game4034 / 4130
- Nim Game I5366 / 5561
- Nim Game II4249 / 4414
- Stair Game2883 / 3126
- Grundy's Game2008 / 2632
- Another Game2277 / 2449
String Algorithms
- Word Combinations6916 / 9808
- String Matching13251 / 17513
- Finding Borders9738 / 10598
- Finding Periods6956 / 7837
- Minimal Rotation3448 / 5069
- Longest Palindrome5103 / 6636
- All Palindromes880 / 985
- Required Substring1962 / 2916
- Palindrome Queries2402 / 2775
- Finding Patterns2265 / 3134
- Counting Patterns2145 / 2622
- Pattern Positions1808 / 2174
- Distinct Substrings2030 / 2403
- Distinct Subsequences1296 / 1373
- Repeating Substring2203 / 2527
- String Functions1934 / 2027
- Inverse Suffix Array350 / 401
- String Transform659 / 785
- Substring Order I1393 / 1541
- Substring Order II938 / 1206
- Substring Distribution1291 / 1397
Geometry
- Point Location Test8362 / 9284
- Line Segment Intersection4967 / 6184
- Polygon Area5705 / 6020
- Point in Polygon3185 / 4010
- Polygon Lattice Points2583 / 2767
- Minimum Euclidean Distance2289 / 3204
- Convex Hull3821 / 4533
- Maximum Manhattan Distances784 / 815
- All Manhattan Distances811 / 893
- Intersection Points2260 / 2434
- Line Segments Trace I437 / 451
- Line Segments Trace II363 / 382
- Lines and Queries I482 / 505
- Lines and Queries II428 / 448
- Area of Rectangles1315 / 1466
- Robot Path359 / 660
Advanced Techniques
- Meet in the Middle7720 / 10486
- Hamming Distance3560 / 3891
- Corner Subgrid Check276 / 649
- Corner Subgrid Count2445 / 2764
- Reachable Nodes2543 / 2729
- Reachability Queries1706 / 2002
- Cut and Paste1743 / 1926
- Substring Reversals1534 / 1660
- Reversals and Sums1559 / 1667
- Necessary Roads2246 / 2304
- Necessary Cities2090 / 2183
- Eulerian Subgraphs894 / 943
- Monster Game I1339 / 1485
- Monster Game II1181 / 1261
- Subarray Squares1676 / 1946
- Houses and Schools909 / 1075
- Knuth Division1087 / 1221
- Apples and Bananas1246 / 1350
- One Bit Positions956 / 1040
- Signal Processing930 / 994
- New Roads Queries2530 / 3045
- Dynamic Connectivity1162 / 1304
- Parcel Delivery902 / 989
- Task Assignment1041 / 1128
- Distinct Routes II687 / 778
Sliding Window Problems
- Sliding Window Sum7366 / 7611
- Sliding Window Minimum5508 / 6272
- Sliding Window Xor5426 / 5502
- Sliding Window Or2436 / 4060
- Sliding Window Distinct Values3814 / 4504
- Sliding Window Mode3003 / 3181
- Sliding Window Mex2835 / 2984
- Sliding Window Median14960 / 17014
- Sliding Window Cost9779 / 11242
- Sliding Window Inversions1534 / 1626
- Sliding Window Advertisement302 / 477
Interactive Problems
- Hidden Integer2725 / 2844
- Hidden Permutation1210 / 1403
- K-th Highest Score546 / 658
- Permuted Binary Strings646 / 664
- Colored Chairs604 / 641
- Inversion Sorting348 / 391
Bitwise Operations
- Counting Bits5935 / 7625
- Maximum Xor Subarray3523 / 4021
- Maximum Xor Subset1260 / 1380
- Number of Subset Xors1106 / 1128
- K Subset Xors570 / 671
- All Subarray Xors341 / 539
- Xor Pyramid Peak2338 / 2814
- Xor Pyramid Diagonal387 / 436
- Xor Pyramid Row336 / 392
- SOS Bit Problem2464 / 2610
- And Subset Count551 / 574
Construction Problems
- Inverse Inversions1965 / 2098
- Monotone Subsequences1191 / 1408
- Third Permutation509 / 629
- Permutation Prime Sums516 / 555
- Chess Tournament1345 / 1553
- Distinct Sums Grid181 / 267
- Filling Trominos295 / 504
- Grid Path Construction159 / 482
Advanced Graph Problems
- Nearest Shops867 / 1113
- Prüfer Code1675 / 1798
- Tree Traversals1372 / 1504
- Course Schedule II2243 / 3154
- Acyclic Graph Edges2401 / 2542
- Strongly Connected Edges1718 / 2004
- Even Outdegree Edges1519 / 1764
- Graph Girth3832 / 4328
- Fixed Length Walk Queries433 / 482
- Transfer Speeds Sum498 / 513
- MST Edge Check805 / 874
- MST Edge Set Check300 / 338
- MST Edge Cost482 / 504
- Network Breakdown1304 / 1418
- Tree Coin Collecting I427 / 461
- Tree Coin Collecting II243 / 278
- Tree Isomorphism I1199 / 1415
- Tree Isomorphism II989 / 1134
- Flight Route Requests562 / 693
- Critical Cities483 / 726
- Visiting Cities743 / 975
- Graph Coloring273 / 319
- Bus Companies319 / 329
- Split into Two Paths127 / 219
- Network Renovation1017 / 1337
- Forbidden Cities939 / 1220
- Creating Offices459 / 599
- New Flight Routes387 / 1002
Counting Problems
- Filled Subgrid Count I716 / 803
- Filled Subgrid Count II392 / 481
- All Letter Subgrid Count I220 / 322
- All Letter Subgrid Count II163 / 212
- Border Subgrid Count I117 / 201
- Border Subgrid Count II128 / 149
- Raab Game II133 / 152
- Empty String1862 / 2253
- Permutation Inversions1107 / 1222
- Counting Bishops434 / 483
- Counting Sequences742 / 798
- Grid Paths II831 / 1043
- Counting Permutations963 / 1087
- Grid Completion247 / 313
- Counting Reorders286 / 399
- Tournament Graph Distribution133 / 142
- Collecting Numbers Distribution139 / 146
- Functional Graph Distribution268 / 329
Additional Problems I
- Shortest Subsequence3205 / 4198
- Distinct Values Sum804 / 828
- Distinct Values Splits566 / 606
- Swap Game2211 / 2832
- Beautiful Permutation II692 / 1070
- Multiplication Table7556 / 8399
- Bubble Sort Rounds I510 / 579
- Bubble Sort Rounds II348 / 388
- Nearest Campsites I219 / 256
- Nearest Campsites II214 / 229
- Advertisement4803 / 5081
- Special Substrings1057 / 1160
- Counting LCM Arrays339 / 370
- Square Subsets260 / 286
- Subarray Sum Constraints521 / 555
- Water Containers Moves210 / 223
- Water Containers Queries244 / 257
- Stack Weights632 / 757
- Maximum Average Subarrays204 / 224
- Subsets with Fixed Average244 / 267
- Two Array Average250 / 279
- Pyramid Array831 / 1001
- Permutation Subsequence293 / 304
- Bit Inversions2510 / 2827
- Writing Numbers793 / 857
- Letter Pair Move Game223 / 310
- Maximum Building I2234 / 2333
- Sorting Methods825 / 881
- Cyclic Array1332 / 1505
- List of Sums527 / 684
Additional Problems II
- Bouncing Ball Steps287 / 318
- Bouncing Ball Cycle118 / 164
- Knight Moves Queries148 / 177
- K Subset Sums I231 / 295
- K Subset Sums II142 / 178
- Increasing Array II881 / 1005
- Food Division560 / 670
- Swap Round Sorting440 / 545
- Binary Subsequences311 / 450
- School Excursion1502 / 1587
- Coin Grid979 / 1143
- Grid Coloring II161 / 209
- Programmers and Artists550 / 766
- Removing Digits II237 / 506
- Coin Arrangement365 / 483
- Replace with Difference156 / 186
- Grid Puzzle I589 / 646
- Grid Puzzle II572 / 626
- Bit Substrings434 / 525
- Reversal Sorting384 / 463
- Book Shop II1385 / 1576
- GCD Subsets482 / 497
- Minimum Cost Pairs164 / 209
- Same Sum Subsets145 / 279
- Mex Grid Queries905 / 1059
- Maximum Building II478 / 587
- Stick Divisions4071 / 4751
- Stick Difference89 / 307
- Coding Company1620 / 2115
- Two Stacks Sorting198 / 621