General
Introductory Problems
- Weird Algorithm34396 / 35823
- Missing Number29012 / 30763
- Repetitions25543 / 26963
- Increasing Array23609 / 24623
- Permutations21017 / 21791
- Number Spiral14677 / 16018
- Two Knights10937 / 11321
- Two Sets11715 / 12764
- Bit Strings14116 / 14923
- Trailing Zeros13314 / 14196
- Coin Piles11546 / 12771
- Palindrome Reorder10215 / 10963
- Gray Code4147 / 4708
- Tower of Hanoi3761 / 3933
- Creating Strings9284 / 9546
- Apple Division8322 / 9704
- Chessboard and Queens4956 / 5049
- Digit Queries2045 / 2550
- Grid Paths2003 / 2640
Sorting and Searching
- Distinct Numbers14808 / 15340
- Apartments10132 / 11700
- Ferris Wheel9577 / 10625
- Concert Tickets7513 / 9243
- Restaurant Customers7666 / 8432
- Movie Festival7385 / 7853
- Sum of Two Values8682 / 9591
- Maximum Subarray Sum8591 / 8952
- Stick Lengths7538 / 8045
- Missing Coin Sum3363 / 3521
- Collecting Numbers3425 / 3758
- Collecting Numbers II1359 / 1786
- Playlist6179 / 7142
- Towers6189 / 6751
- Traffic Lights4711 / 5362
- Josephus Problem I1891 / 2208
- Josephus Problem II1133 / 1488
- Nested Ranges Check911 / 1111
- Nested Ranges Count731 / 810
- Room Allocation3686 / 4443
- Factory Machines4197 / 4587
- Tasks and Deadlines4147 / 4238
- Reading Books3510 / 3789
- Sum of Three Values4580 / 5136
- Sum of Four Values3214 / 3625
- Nearest Smaller Values4003 / 4203
- Subarray Sums I4672 / 5179
- Subarray Sums II4327 / 4850
- Subarray Divisibility4043 / 4334
- Subarray Distinct Values1384 / 1479
- Array Division3294 / 3501
- Sliding Median2587 / 3053
- Sliding Cost1815 / 2067
- Movie Festival II2062 / 2541
- Maximum Subarray Sum II1980 / 2374
Dynamic Programming
- Dice Combinations13506 / 14355
- Minimizing Coins11749 / 12549
- Coin Combinations I10944 / 11797
- Coin Combinations II9139 / 10429
- Removing Digits10289 / 10470
- Grid Paths9464 / 9761
- Book Shop8540 / 9415
- Array Description5916 / 6675
- Counting Towers2032 / 2172
- Edit Distance6397 / 6800
- Rectangle Cutting5495 / 5989
- Money Sums6386 / 6619
- Removal Game4626 / 5070
- Two Sets II5169 / 5620
- Increasing Subsequence5171 / 5938
- Projects3360 / 3823
- Elevator Rides1290 / 1746
- Counting Tilings690 / 775
- Counting Numbers886 / 994
Graph Algorithms
- Counting Rooms9104 / 9730
- Labyrinth5684 / 7030
- Building Roads7304 / 7643
- Message Route6289 / 6570
- Building Teams6068 / 6355
- Round Trip4890 / 5359
- Monsters2719 / 3461
- Shortest Routes I4988 / 5574
- Shortest Routes II4274 / 4614
- High Score2483 / 3458
- Flight Discount2895 / 3413
- Cycle Finding2384 / 2812
- Flight Routes2025 / 2234
- Round Trip II2353 / 2795
- Course Schedule3245 / 3373
- Longest Flight Route2098 / 2774
- Game Routes2537 / 2677
- Investigation1680 / 1831
- Planets Queries I1679 / 1796
- Planets Queries II718 / 866
- Planets Cycles1001 / 1120
- Road Reparation2068 / 2147
- Road Construction2063 / 2130
- Flight Routes Check1938 / 2132
- Planets and Kingdoms1663 / 1716
- Giant Pizza770 / 875
- Coin Collector1109 / 1223
- Mail Delivery983 / 1101
- De Bruijn Sequence607 / 631
- Teleporters Path736 / 885
- Hamiltonian Flights854 / 990
- Knight's Tour554 / 642
- Download Speed922 / 1014
- Police Chase700 / 759
- School Dance722 / 751
- Distinct Routes441 / 634
Range Queries
- Static Range Sum Queries5870 / 6125
- Static Range Minimum Queries4514 / 4837
- Dynamic Range Sum Queries4514 / 4724
- Dynamic Range Minimum Queries4042 / 4147
- Range Xor Queries4197 / 4267
- Range Update Queries3257 / 3508
- Forest Queries2977 / 3089
- Hotel Queries2356 / 2518
- List Removals2004 / 2126
- Salary Queries1525 / 1814
- Prefix Sum Queries719 / 778
- Pizzeria Queries575 / 599
- Subarray Sum Queries1311 / 1465
- Distinct Values Queries1281 / 1498
- Increasing Array Queries304 / 358
- Forest Queries II962 / 1025
- Range Updates and Sums970 / 1183
- Polynomial Queries779 / 910
- Range Queries and Copies522 / 547
Tree Algorithms
- Subordinates4813 / 5166
- Tree Matching2580 / 3125
- Tree Diameter3925 / 4177
- Tree Distances I2729 / 3000
- Tree Distances II2274 / 2368
- Company Queries I2438 / 2592
- Company Queries II2365 / 2473
- Distance Queries2329 / 2486
- Counting Paths1397 / 1489
- Subtree Queries1658 / 1768
- Path Queries1347 / 1412
- Path Queries II399 / 486
- Distinct Colors1224 / 1460
- Finding a Centroid694 / 719
- Fixed-Length Paths I349 / 390
- Fixed-Length Paths II272 / 298
Mathematics
- Josephus Queries384 / 501
- Exponentiation4875 / 5374
- Exponentiation II3385 / 4290
- Counting Divisors3744 / 4348
- Common Divisors2657 / 3089
- Sum of Divisors1490 / 2448
- Divisor Analysis532 / 752
- Prime Multiples562 / 696
- Counting Coprime Pairs364 / 464
- Binomial Coefficients1855 / 2125
- Creating Strings II1547 / 1686
- Distributing Apples1448 / 1563
- Christmas Party1299 / 1396
- Bracket Sequences I485 / 540
- Bracket Sequences II211 / 257
- Counting Necklaces247 / 266
- Counting Grids187 / 201
- Fibonacci Numbers1578 / 2026
- Throwing Dice946 / 1031
- Graph Paths I806 / 864
- Graph Paths II675 / 698
- Dice Probability798 / 848
- Moving Robots429 / 456
- Candy Lottery588 / 604
- Inversion Probability514 / 525
- Stick Game776 / 795
- Nim Game I953 / 987
- Nim Game II783 / 815
- Stair Game522 / 599
- Grundy's Game192 / 248
- Another Game179 / 195
String Algorithms
- Word Combinations796 / 1278
- String Matching1749 / 2386
- Finding Borders1176 / 1343
- Finding Periods750 / 869
- Minimal Rotation546 / 822
- Longest Palindrome681 / 943
- Required Substring317 / 552
- Palindrome Queries163 / 203
- Finding Patterns179 / 265
- Counting Patterns180 / 224
- Pattern Positions158 / 193
- Distinct Substrings169 / 203
- Repeating Substring156 / 168
- String Functions150 / 156
- Substring Order I112 / 118
- Substring Order II79 / 96
- Substring Distribution112 / 123
Geometry
- Point Location Test866 / 953
- Line Segment Intersection515 / 649
- Polygon Area586 / 608
- Point in Polygon323 / 416
- Polygon Lattice Points275 / 286
- Minimum Euclidean Distance238 / 328
- Convex Hull375 / 457
Advanced Techniques
- Meet in the Middle909 / 1226
- Hamming Distance389 / 427
- Beautiful Subgrids208 / 267
- Reachable Nodes212 / 239
- Reachability Queries163 / 189
- Cut and Paste130 / 147
- Substring Reversals117 / 123
- Reversals and Sums114 / 119
- Necessary Roads179 / 181
- Necessary Cities161 / 169
- Eulerian Subgraphs88 / 92
- Monster Game I107 / 118
- Monster Game II106 / 111
- Subarray Squares123 / 145
- Houses and Schools84 / 93
- Knuth Division101 / 115
- Apples and Bananas102 / 113
- One Bit Positions98 / 111
- Signal Processing95 / 99
- New Roads Queries133 / 153
- Dynamic Connectivity83 / 90
- Parcel Delivery69 / 81
- Task Assignment70 / 73
- Distinct Routes II66 / 76
Additional Problems
- Shortest Subsequence798 / 1062
- Counting Bits861 / 1120
- Swap Game332 / 453
- Prüfer Code353 / 373
- Acyclic Graph Edges482 / 515
- Strongly Connected Edges144 / 154
- Even Outdegree Edges131 / 157
- Multiplication Table330 / 360
- Advertisement612 / 646
- Special Substrings108 / 118
- Permutation Inversions116 / 133
- Maximum Xor Subarray470 / 508
- Movie Festival Queries220 / 252
- Chess Tournament259 / 300
- Tree Traversals261 / 269
- Network Renovation194 / 283
- Graph Girth456 / 516
- Intersection Points311 / 338
- Inverse Inversions120 / 124
- Monotone Subsequences73 / 84
- String Reorder190 / 210
- Stack Weights58 / 65
- Pyramid Array173 / 209
- Increasing Subsequence II411 / 440
- String Removals230 / 263
- Bit Inversions442 / 488
- Xor Pyramid162 / 205
- Writing Numbers218 / 238
- String Transform144 / 169
- Letter Pair Move Game20 / 28
- Maximum Building I408 / 419
- Sorting Methods228 / 242
- Cyclic Array150 / 198
- List of Sums65 / 90
- Increasing Array II78 / 90
- Food Division141 / 169
- Bit Problem236 / 257
- Swap Round Sorting95 / 126
- Binary Subsequences21 / 42
- Tree Isomorphism I186 / 241
- Counting Sequences72 / 77
- Critical Cities90 / 135
- School Excursion253 / 269
- Coin Grid145 / 176
- Robot Path70 / 133
- Programmers and Artists42 / 54
- Course Schedule II283 / 410
- Removing Digits II25 / 44
- Coin Arrangement27 / 40
- Counting Bishops39 / 43
- Grid Puzzle I62 / 72
- Grid Puzzle II44 / 48
- Empty String225 / 287
- Grid Paths192 / 244
- Bit Substrings47 / 52
- Reversal Sorting40 / 54
- Counting Reorders24 / 33
- Book Shop II212 / 236
- Network Breakdown201 / 210
- Visiting Cities163 / 217
- Missing Coin Sum Queries33 / 51
- Number Grid256 / 313
- Maximum Building II108 / 132
- Filling Trominos26 / 44
- Stick Divisions489 / 582
- Coding Company216 / 275
- Flight Route Requests122 / 135
- Two Stacks Sorting16 / 61
- Tree Isomorphism II166 / 188
- Forbidden Cities131 / 162
- Area of Rectangles195 / 225
- Grid Completion19 / 26
- Creating Offices79 / 114
- Permutations II225 / 252
- Functional Graph Distribution19 / 22
- New Flight Routes93 / 195
- Grid Path Construction14 / 23