General
Introductory Problems
- Weird Algorithm154374 / 161578
- Missing Number133184 / 139585
- Repetitions115924 / 120586
- Increasing Array109007 / 112884
- Permutations95880 / 98801
- Number Spiral67788 / 73830
- Two Knights51823 / 53445
- Two Sets56360 / 60649
- Bit Strings64483 / 68061
- Trailing Zeros60073 / 63890
- Coin Piles53199 / 58189
- Palindrome Reorder49488 / 52227
- Gray Code33079 / 37171
- Tower of Hanoi30696 / 31928
- Creating Strings41735 / 42822
- Apple Division41861 / 47285
- Chessboard and Queens25235 / 25690
- Raab Game I4467 / 5048
- Mex Grid Construction4310 / 4574
- Knight Moves Grid4280 / 4379
- Grid Coloring I3588 / 3711
- Digit Queries17733 / 20621
- String Reorder3326 / 3862
- Grid Path Description9877 / 12829
Sorting and Searching
- Distinct Numbers76026 / 82199
- Apartments56527 / 62768
- Ferris Wheel54301 / 58577
- Concert Tickets43600 / 50749
- Restaurant Customers44341 / 47851
- Movie Festival42700 / 45204
- Sum of Two Values49754 / 55674
- Maximum Subarray Sum47994 / 50113
- Stick Lengths42861 / 44829
- Missing Coin Sum32294 / 33470
- Collecting Numbers33139 / 35475
- Collecting Numbers II13855 / 17692
- Playlist33102 / 37782
- Towers33381 / 35759
- Traffic Lights25888 / 28961
- Distinct Values Subarrays5851 / 6987
- Distinct Values Subsequences4584 / 5074
- Josephus Problem I19776 / 21801
- Josephus Problem II10708 / 14768
- Nested Ranges Check11403 / 13109
- Nested Ranges Count7676 / 9065
- Room Allocation19460 / 22317
- Factory Machines27744 / 30213
- Tasks and Deadlines22274 / 22753
- Reading Books18061 / 19341
- Sum of Three Values26515 / 29359
- Sum of Four Values16445 / 18318
- Nearest Smaller Values22017 / 22772
- Subarray Sums I29236 / 31167
- Subarray Sums II26551 / 31494
- Subarray Divisibility24167 / 26321
- Distinct Values Subarrays II14531 / 15988
- Array Division22893 / 24097
- Movie Festival II12235 / 14760
- Maximum Subarray Sum II11309 / 13497
Dynamic Programming
- Dice Combinations79081 / 83642
- Minimizing Coins68299 / 73366
- Coin Combinations I62383 / 67538
- Coin Combinations II52661 / 59612
- Removing Digits58679 / 59868
- Grid Paths I55207 / 56774
- Book Shop49361 / 54282
- Array Description36249 / 40263
- Counting Towers22096 / 23432
- Edit Distance36531 / 38557
- Longest Common Subsequence8843 / 9161
- Rectangle Cutting30162 / 32945
- Minimal Grid Path3759 / 6964
- Money Sums35756 / 37112
- Removal Game21244 / 28579
- Two Sets II28116 / 30273
- Mountain Range2659 / 4902
- Increasing Subsequence28792 / 32330
- Projects19806 / 22142
- Elevator Rides12684 / 15975
- Counting Tilings7419 / 8085
- Counting Numbers10346 / 11671
- Increasing Subsequence II4201 / 4881
Graph Algorithms
- Counting Rooms54212 / 56948
- Labyrinth37538 / 44985
- Building Roads47183 / 48887
- Message Route40636 / 42247
- Building Teams38462 / 40547
- Round Trip30541 / 33257
- Monsters20841 / 24606
- Shortest Routes I33357 / 36801
- Shortest Routes II27173 / 30454
- High Score16549 / 23379
- Flight Discount21396 / 25029
- Cycle Finding15251 / 18711
- Flight Routes14821 / 16535
- Round Trip II16857 / 18920
- Course Schedule22112 / 23359
- Longest Flight Route15586 / 19356
- Game Routes17449 / 18689
- Investigation12943 / 13914
- Planets Queries I11327 / 13247
- Planets Queries II4086 / 5176
- Planets Cycles6934 / 7745
- Road Reparation16974 / 17693
- Road Construction18613 / 19192
- Flight Routes Check15080 / 16344
- Planets and Kingdoms12029 / 12526
- Giant Pizza5036 / 5538
- Coin Collector7873 / 8729
- Mail Delivery6563 / 7182
- De Bruijn Sequence3443 / 3604
- Teleporters Path4984 / 5701
- Hamiltonian Flights7499 / 8561
- Knight's Tour2815 / 3405
- Download Speed4948 / 6642
- Police Chase3961 / 4443
- School Dance4349 / 4597
- Distinct Routes3073 / 4025
Range Queries
- Static Range Sum Queries37817 / 39500
- Static Range Minimum Queries26335 / 28194
- Dynamic Range Sum Queries27328 / 28526
- Dynamic Range Minimum Queries24756 / 25338
- Range Xor Queries25620 / 25962
- Range Update Queries20334 / 21788
- Forest Queries20903 / 21686
- Hotel Queries14752 / 15656
- List Removals12239 / 12875
- Salary Queries9175 / 11575
- Prefix Sum Queries7842 / 8495
- Pizzeria Queries6307 / 6542
- Visible Buildings Queries1435 / 1571
- Range Interval Queries1119 / 1496
- Subarray Sum Queries7496 / 8129
- Subarray Sum Queries II1555 / 1619
- Distinct Values Queries6934 / 8557
- Distinct Values Queries II909 / 1042
- Increasing Array Queries2662 / 3054
- Movie Festival Queries1349 / 1500
- Forest Queries II4463 / 4807
- Range Updates and Sums6004 / 7126
- Polynomial Queries4391 / 5147
- Range Queries and Copies3161 / 3382
- Missing Coin Sum Queries675 / 897
Tree Algorithms
- Subordinates31225 / 33391
- Tree Matching17731 / 20639
- Tree Diameter25461 / 26985
- Tree Distances I19473 / 20916
- Tree Distances II15947 / 16626
- Company Queries I17724 / 18640
- Company Queries II16658 / 17469
- Distance Queries15095 / 16187
- Counting Paths9461 / 10033
- Subtree Queries11337 / 12098
- Path Queries9104 / 9649
- Path Queries II3664 / 5561
- Distinct Colors8737 / 9645
- Finding a Centroid7062 / 7351
- Fixed-Length Paths I3369 / 4365
- Fixed-Length Paths II1586 / 2902
Mathematics
- Josephus Queries4862 / 6127
- Exponentiation24691 / 26375
- Exponentiation II17396 / 20840
- Counting Divisors22387 / 25267
- Common Divisors14641 / 16997
- Sum of Divisors8182 / 12255
- Divisor Analysis5594 / 7504
- Prime Multiples6479 / 7567
- Counting Coprime Pairs4218 / 4922
- Next Prime1741 / 1998
- Binomial Coefficients10421 / 11558
- Creating Strings II8744 / 9227
- Distributing Apples8399 / 9031
- Christmas Party6828 / 7323
- Permutation Order826 / 844
- Permutation Rounds1036 / 1149
- Bracket Sequences I4630 / 5041
- Bracket Sequences II2416 / 2769
- Counting Necklaces2231 / 2416
- Counting Grids1840 / 1964
- Fibonacci Numbers7099 / 8898
- Throwing Dice3687 / 4010
- Graph Paths I3500 / 3755
- Graph Paths II2923 / 3065
- System of Linear Equations386 / 429
- Sum of Four Squares582 / 697
- Triangle Number Sums506 / 629
- Dice Probability3170 / 3417
- Moving Robots1625 / 1720
- Candy Lottery1474 / 3058
- Inversion Probability375 / 2304
- Stick Game3573 / 3660
- Nim Game I4731 / 4911
- Nim Game II3745 / 3897
- Stair Game2532 / 2756
- Grundy's Game1755 / 2310
- Another Game1986 / 2141
String Algorithms
- Word Combinations6043 / 8756
- String Matching11695 / 15623
- Finding Borders8539 / 9342
- Finding Periods6062 / 6888
- Minimal Rotation2948 / 4478
- Longest Palindrome4465 / 5921
- All Palindromes567 / 647
- Required Substring1691 / 2584
- Palindrome Queries2082 / 2424
- Finding Patterns1944 / 2766
- Counting Patterns1840 / 2286
- Pattern Positions1541 / 1886
- Distinct Substrings1759 / 2099
- Distinct Subsequences1100 / 1173
- Repeating Substring1895 / 2206
- String Functions1651 / 1729
- Inverse Suffix Array188 / 228
- String Transform534 / 651
- Substring Order I1191 / 1333
- Substring Order II790 / 1026
- Substring Distribution1109 / 1205
Geometry
- Point Location Test7484 / 8344
- Line Segment Intersection4446 / 5572
- Polygon Area5139 / 5438
- Point in Polygon2828 / 3616
- Polygon Lattice Points2397 / 2479
- Minimum Euclidean Distance1996 / 2869
- Convex Hull3433 / 4113
- Maximum Manhattan Distances544 / 561
- All Manhattan Distances539 / 589
- Intersection Points2009 / 2168
- Line Segments Trace I296 / 306
- Line Segments Trace II243 / 256
- Lines and Queries I335 / 346
- Lines and Queries II287 / 297
- Area of Rectangles1157 / 1291
- Robot Path306 / 564
Advanced Techniques
- Meet in the Middle6799 / 9445
- Hamming Distance3269 / 3562
- Corner Subgrid Check294 / 459
- Corner Subgrid Count2269 / 2546
- Reachable Nodes2306 / 2482
- Reachability Queries1528 / 1805
- Cut and Paste1534 / 1711
- Substring Reversals1343 / 1463
- Reversals and Sums1353 / 1456
- Necessary Roads1969 / 2022
- Necessary Cities1815 / 1903
- Eulerian Subgraphs804 / 847
- Monster Game I1163 / 1295
- Monster Game II1038 / 1113
- Subarray Squares1417 / 1675
- Houses and Schools783 / 937
- Knuth Division958 / 1081
- Apples and Bananas1084 / 1179
- One Bit Positions861 / 941
- Signal Processing817 / 876
- New Roads Queries2211 / 2687
- Dynamic Connectivity1011 / 1140
- Parcel Delivery783 / 866
- Task Assignment923 / 982
- Distinct Routes II590 / 675
Sliding Window Problems
- Sliding Window Sum4601 / 4785
- Sliding Window Minimum3424 / 3923
- Sliding Window Xor3380 / 3424
- Sliding Window Or1505 / 2633
- Sliding Window Distinct Values2238 / 2877
- Sliding Window Mode1956 / 2062
- Sliding Window Mex1771 / 1868
- Sliding Window Median13752 / 15712
- Sliding Window Cost9030 / 10425
- Sliding Window Inversions1005 / 1072
- Sliding Window Advertisement196 / 315
Interactive Problems
- Hidden Integer1888 / 1953
- Hidden Permutation803 / 951
- K-th Highest Score352 / 430
- Permuted Binary Strings442 / 454
- Colored Chairs393 / 414
- Inversion Sorting228 / 251
Bitwise Operations
- Counting Bits4864 / 6266
- Maximum Xor Subarray2912 / 3300
- Maximum Xor Subset859 / 941
- Number of Subset Xors757 / 774
- K Subset Xors369 / 440
- All Subarray Xors232 / 383
- Xor Pyramid Peak1974 / 2410
- Xor Pyramid Diagonal268 / 304
- Xor Pyramid Row219 / 264
- SOS Bit Problem2089 / 2225
- And Subset Count353 / 364
Construction Problems
- Inverse Inversions1537 / 1636
- Monotone Subsequences942 / 1106
- Third Permutation341 / 406
- Permutation Prime Sums343 / 370
- Chess Tournament1177 / 1360
- Distinct Sums Grid100 / 161
- Filling Trominos232 / 413
- Grid Path Construction119 / 426
Advanced Graph Problems
- Nearest Shops602 / 779
- Prüfer Code1501 / 1617
- Tree Traversals1187 / 1308
- Course Schedule II1883 / 2702
- Acyclic Graph Edges2199 / 2335
- Strongly Connected Edges1550 / 1722
- Even Outdegree Edges1315 / 1541
- Graph Girth3358 / 3829
- Fixed Length Walk Queries314 / 344
- Transfer Speeds Sum360 / 371
- MST Edge Check516 / 560
- MST Edge Set Check193 / 223
- MST Edge Cost324 / 338
- Network Breakdown1007 / 1069
- Tree Coin Collecting I277 / 306
- Tree Coin Collecting II146 / 173
- Tree Isomorphism I1071 / 1284
- Tree Isomorphism II876 / 1018
- Flight Route Requests480 / 588
- Critical Cities403 / 626
- Visiting Cities665 / 884
- Graph Coloring200 / 235
- Bus Companies228 / 236
- Split into Two Paths77 / 146
- Network Renovation925 / 1234
- Forbidden Cities820 / 1069
- Creating Offices407 / 531
- New Flight Routes310 / 835
Counting Problems
- Filled Subgrid Count I482 / 538
- Filled Subgrid Count II254 / 315
- All Letter Subgrid Count I138 / 216
- All Letter Subgrid Count II108 / 137
- Border Subgrid Count I81 / 139
- Border Subgrid Count II83 / 99
- Raab Game II87 / 103
- Empty String1603 / 1957
- Permutation Inversions1004 / 1110
- Counting Bishops377 / 422
- Counting Sequences636 / 692
- Grid Paths II736 / 921
- Counting Permutations861 / 975
- Grid Completion218 / 277
- Counting Reorders230 / 337
- Tournament Graph Distribution91 / 96
- Collecting Numbers Distribution97 / 106
- Functional Graph Distribution235 / 291
Additional Problems I
- Shortest Subsequence2955 / 3902
- Distinct Values Sum566 / 585
- Distinct Values Splits404 / 429
- Swap Game2037 / 2579
- Beautiful Permutation II400 / 600
- Multiplication Table6607 / 7366
- Bubble Sort Rounds I336 / 382
- Bubble Sort Rounds II213 / 244
- Nearest Campsites I150 / 176
- Nearest Campsites II149 / 160
- Advertisement4239 / 4492
- Special Substrings962 / 1057
- Counting LCM Arrays224 / 246
- Square Subsets189 / 211
- Subarray Sum Constraints293 / 314
- Water Containers Moves139 / 147
- Water Containers Queries174 / 181
- Stack Weights575 / 683
- Maximum Average Subarrays144 / 160
- Subsets with Fixed Average175 / 192
- Two Array Average168 / 189
- Pyramid Array717 / 874
- Permutation Subsequence191 / 195
- Bit Inversions2284 / 2592
- Writing Numbers725 / 783
- Letter Pair Move Game196 / 275
- Maximum Building I2026 / 2116
- Sorting Methods755 / 809
- Cyclic Array1159 / 1319
- List of Sums469 / 615
Additional Problems II
- Bouncing Ball Steps191 / 211
- Bouncing Ball Cycle74 / 109
- Knight Moves Queries100 / 123
- K Subset Sums I152 / 202
- K Subset Sums II77 / 108
- Increasing Array II776 / 894
- Food Division503 / 609
- Swap Round Sorting402 / 498
- Binary Subsequences284 / 418
- School Excursion1349 / 1432
- Coin Grid852 / 997
- Grid Coloring II113 / 151
- Programmers and Artists483 / 679
- Removing Digits II211 / 464
- Coin Arrangement320 / 432
- Replace with Difference107 / 129
- Grid Puzzle I518 / 571
- Grid Puzzle II493 / 546
- Bit Substrings379 / 462
- Reversal Sorting345 / 420
- Book Shop II1188 / 1363
- GCD Subsets354 / 363
- Minimum Cost Pairs92 / 130
- Same Sum Subsets99 / 182
- Mex Grid Queries825 / 970
- Maximum Building II437 / 538
- Stick Divisions3732 / 4384
- Stick Difference39 / 194
- Coding Company1451 / 1905
- Two Stacks Sorting171 / 545