CSES Problem Set

General

• Introduction
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• Statistics

Introductory Problems

• Weird Algorithm147855 / 154846
• Missing Number127571 / 133789
• Repetitions111066 / 115626
• Increasing Array104382 / 108177
• Permutations91733 / 94587
• Number Spiral64862 / 70712
• Two Knights49429 / 51011
• Two Sets53794 / 57947
• Bit Strings61621 / 65079
• Trailing Zeros57555 / 61239
• Coin Piles50929 / 55760
• Palindrome Reorder47374 / 50037
• Gray Code31492 / 35437
• Tower of Hanoi29040 / 30212
• Creating Strings39898 / 40947
• Apple Division39915 / 45161
• Chessboard and Queens24106 / 24541
• Raab Game I3487 / 3987
• Mex Grid Construction3362 / 3593
• Knight Moves Grid3358 / 3437
• Grid Coloring I2775 / 2875
• Digit Queries16982 / 19832
• String Reorder2696 / 3141
• Grid Path Description9462 / 12316

Sorting and Searching

• Distinct Numbers72087 / 78040
• Apartments53401 / 59453
• Ferris Wheel51257 / 55422
• Concert Tickets41344 / 48205
• Restaurant Customers42010 / 45384
• Movie Festival40315 / 42724
• Sum of Two Values47077 / 52799
• Maximum Subarray Sum45586 / 47643
• Stick Lengths40689 / 42606
• Missing Coin Sum30543 / 31677
• Collecting Numbers31308 / 33572
• Collecting Numbers II12969 / 16646
• Playlist31392 / 35980
• Towers31839 / 34120
• Traffic Lights24627 / 27604
• Distinct Values Subarrays5180 / 5452
• Distinct Values Subsequences3581 / 3999
• Josephus Problem I18679 / 20653
• Josephus Problem II10042 / 13910
• Nested Ranges Check10706 / 12343
• Nested Ranges Count7250 / 8573
• Room Allocation18508 / 21291
• Factory Machines26234 / 28655
• Tasks and Deadlines21216 / 21680
• Reading Books17162 / 18393
• Sum of Three Values25141 / 27889
• Sum of Four Values15653 / 17499
• Nearest Smaller Values20942 / 21664
• Subarray Sums I27704 / 29602
• Subarray Sums II25084 / 29890
• Subarray Divisibility23012 / 25124
• Distinct Values Subarrays II13682 / 15126
• Array Division21746 / 22900
• Movie Festival II11582 / 14008
• Maximum Subarray Sum II10710 / 12831

Dynamic Programming

• Dice Combinations75437 / 79858
• Minimizing Coins65183 / 70081
• Coin Combinations I59485 / 64463
• Coin Combinations II50263 / 57009
• Removing Digits56068 / 57231
• Grid Paths I52647 / 54154
• Book Shop47068 / 51854
• Array Description34642 / 38549
• Counting Towers20997 / 22262
• Edit Distance34888 / 36843
• Longest Common Subsequence7092 / 7360
• Rectangle Cutting28965 / 31666
• Minimal Grid Path3025 / 5774
• Money Sums34370 / 35705
• Removal Game20172 / 27466
• Two Sets II27089 / 29202
• Mountain Range2126 / 4080
• Increasing Subsequence27632 / 31045
• Projects19087 / 21389
• Elevator Rides12097 / 15291
• Counting Tilings7053 / 7706
• Counting Numbers9632 / 10900
• Increasing Subsequence II3716 / 4321

Graph Algorithms

• Counting Rooms51863 / 54517
• Labyrinth35825 / 43049
• Building Roads45236 / 46885
• Message Route38864 / 40424
• Building Teams36723 / 38770
• Round Trip29198 / 31856
• Monsters19864 / 23532
• Shortest Routes I31842 / 35236
• Shortest Routes II25960 / 29163
• High Score15665 / 22393
• Flight Discount20328 / 23887
• Cycle Finding14463 / 17843
• Flight Routes14127 / 15801
• Round Trip II16126 / 18161
• Course Schedule21137 / 22376
• Longest Flight Route14822 / 18531
• Game Routes16672 / 17896
• Investigation12347 / 13296
• Planets Queries I10737 / 12612
• Planets Queries II3828 / 4867
• Planets Cycles6571 / 7348
• Road Reparation16156 / 16849
• Road Construction17727 / 18295
• Flight Routes Check14423 / 15661
• Planets and Kingdoms11599 / 12015
• Giant Pizza4751 / 5241
• Coin Collector7474 / 8320
• Mail Delivery6252 / 6856
• De Bruijn Sequence3258 / 3412
• Teleporters Path4724 / 5433
• Hamiltonian Flights7086 / 8102
• Knight's Tour2632 / 3215
• Download Speed4664 / 6328
• Police Chase3730 / 4204
• School Dance4132 / 4375
• Distinct Routes2893 / 3814

Range Queries

• Static Range Sum Queries35872 / 37486
• Static Range Minimum Queries25208 / 27007
• Dynamic Range Sum Queries26215 / 27377
• Dynamic Range Minimum Queries23748 / 24316
• Range Xor Queries24550 / 24889
• Range Update Queries19398 / 20823
• Forest Queries19894 / 20653
• Hotel Queries14028 / 14920
• List Removals11682 / 12304
• Salary Queries8636 / 10965
• Prefix Sum Queries7384 / 8019
• Pizzeria Queries5970 / 6202
• Visible Buildings Queries1155 / 1273
• Range Interval Queries903 / 1204
• Subarray Sum Queries7155 / 7780
• Subarray Sum Queries II1214 / 1283
• Distinct Values Queries6559 / 8159
• Distinct Values Queries II704 / 826
• Increasing Array Queries2523 / 2897
• Movie Festival Queries1221 / 1356
• Forest Queries II4295 / 4625
• Range Updates and Sums5707 / 6804
• Polynomial Queries4198 / 4929
• Range Queries and Copies2992 / 3210
• Missing Coin Sum Queries600 / 795

Tree Algorithms

• Subordinates29903 / 32010
• Tree Matching16975 / 19818
• Tree Diameter24335 / 25817
• Tree Distances I18592 / 20005
• Tree Distances II15257 / 15910
• Company Queries I16907 / 17799
• Company Queries II15833 / 16619
• Distance Queries14438 / 15511
• Counting Paths9038 / 9596
• Subtree Queries10853 / 11589
• Path Queries8668 / 9190
• Path Queries II3497 / 5247
• Distinct Colors8364 / 9256
• Finding a Centroid6724 / 7007
• Fixed-Length Paths I3166 / 4132
• Fixed-Length Paths II1477 / 2734

Mathematics

• Josephus Queries4570 / 5765
• Exponentiation23483 / 25074
• Exponentiation II16643 / 19993
• Counting Divisors21343 / 24123
• Common Divisors14008 / 16302
• Sum of Divisors7815 / 11781
• Divisor Analysis5318 / 7161
• Prime Multiples6059 / 7107
• Counting Coprime Pairs3970 / 4657
• Next Prime1392 / 1598
• Binomial Coefficients9861 / 10964
• Creating Strings II8322 / 8791
• Distributing Apples7993 / 8609
• Christmas Party6441 / 6930
• Permutation Order642 / 656
• Permutation Rounds749 / 846
• Bracket Sequences I4429 / 4827
• Bracket Sequences II2286 / 2630
• Counting Necklaces2113 / 2292
• Counting Grids1721 / 1839
• Fibonacci Numbers6803 / 8554
• Throwing Dice3532 / 3842
• Graph Paths I3349 / 3597
• Graph Paths II2806 / 2942
• System of Linear Equations320 / 346
• Sum of Four Squares489 / 566
• Triangle Number Sums414 / 521
• Dice Probability3039 / 3283
• Moving Robots1559 / 1651
• Candy Lottery1324 / 2893
• Inversion Probability311 / 2214
• Stick Game3409 / 3491
• Nim Game I4501 / 4672
• Nim Game II3555 / 3704
• Stair Game2410 / 2624
• Grundy's Game1656 / 2192
• Another Game1871 / 2020

String Algorithms

• Word Combinations5744 / 8371
• String Matching11175 / 14992
• Finding Borders8171 / 8942
• Finding Periods5816 / 6614
• Minimal Rotation2824 / 4330
• Longest Palindrome4292 / 5672
• All Palindromes478 / 545
• Required Substring1610 / 2481
• Palindrome Queries2004 / 2340
• Finding Patterns1851 / 2655
• Counting Patterns1749 / 2182
• Pattern Positions1458 / 1789
• Distinct Substrings1668 / 1998
• Distinct Subsequences1044 / 1114
• Repeating Substring1809 / 2115
• String Functions1582 / 1657
• Inverse Suffix Array157 / 186
• String Transform502 / 614
• Substring Order I1131 / 1270
• Substring Order II749 / 972
• Substring Distribution1050 / 1142

Geometry

• Point Location Test7107 / 7947
• Line Segment Intersection4223 / 5327
• Polygon Area4911 / 5208
• Point in Polygon2695 / 3412
• Polygon Lattice Points2279 / 2360
• Minimum Euclidean Distance1972 / 2739
• Convex Hull3239 / 3907
• Maximum Manhattan Distances443 / 455
• All Manhattan Distances447 / 489
• Intersection Points1907 / 2054
• Line Segments Trace I243 / 251
• Line Segments Trace II196 / 207
• Lines and Queries I265 / 273
• Lines and Queries II226 / 234
• Area of Rectangles1085 / 1214
• Robot Path305 / 524

Advanced Techniques

• Meet in the Middle6505 / 9115
• Hamming Distance3180 / 3465
• Corner Subgrid Check237 / 382
• Corner Subgrid Count2200 / 2470
• Reachable Nodes2202 / 2370
• Reachability Queries1465 / 1736
• Cut and Paste1462 / 1629
• Substring Reversals1283 / 1400
• Reversals and Sums1288 / 1390
• Necessary Roads1885 / 1929
• Necessary Cities1749 / 1835
• Eulerian Subgraphs766 / 807
• Monster Game I1112 / 1240
• Monster Game II989 / 1063
• Subarray Squares1324 / 1577
• Houses and Schools740 / 890
• Knuth Division897 / 1017
• Apples and Bananas1007 / 1095
• One Bit Positions809 / 887
• Signal Processing758 / 815
• New Roads Queries2109 / 2570
• Dynamic Connectivity947 / 1072
• Parcel Delivery731 / 811
• Task Assignment855 / 910
• Distinct Routes II551 / 635

Sliding Window Problems

• Sliding Window Sum3557 / 3716
• Sliding Window Minimum2756 / 3144
• Sliding Window Xor2658 / 2689
• Sliding Window Or1138 / 2071
• Sliding Window Distinct Values2222 / 2263
• Sliding Window Mode1552 / 1634
• Sliding Window Mex1386 / 1463
• Sliding Window Median13216 / 15134
• Sliding Window Cost8770 / 10130
• Sliding Window Inversions781 / 839
• Sliding Window Advertisement152 / 246

Interactive Problems

• Hidden Integer1521 / 1574
• Hidden Permutation643 / 778
• K-th Highest Score273 / 331
• Permuted Binary Strings362 / 371
• Colored Chairs313 / 330
• Inversion Sorting185 / 198

Bitwise Operations

• Counting Bits4465 / 5748
• Maximum Xor Subarray2722 / 3067
• Maximum Xor Subset705 / 760
• Number of Subset Xors611 / 622
• K Subset Xors288 / 344
• All Subarray Xors194 / 307
• Xor Pyramid Peak1845 / 2262
• Xor Pyramid Diagonal224 / 254
• Xor Pyramid Row183 / 215
• SOS Bit Problem1916 / 2043
• And Subset Count278 / 282

Construction Problems

• Inverse Inversions1388 / 1478
• Monotone Subsequences835 / 982
• Third Permutation278 / 325
• Permutation Prime Sums273 / 295
• Chess Tournament1107 / 1280
• Distinct Sums Grid75 / 127
• Filling Trominos228 / 393
• Grid Path Construction115 / 417

Advanced Graph Problems

• Nearest Shops513 / 668
• Prüfer Code1426 / 1541
• Tree Traversals1123 / 1237
• Course Schedule II1763 / 2538
• Acyclic Graph Edges2102 / 2233
• Strongly Connected Edges1461 / 1621
• Even Outdegree Edges1247 / 1469
• Graph Girth3180 / 3642
• Fixed Length Walk Queries261 / 286
• Transfer Speeds Sum299 / 307
• MST Edge Check393 / 420
• MST Edge Set Check163 / 184
• MST Edge Cost269 / 282
• Network Breakdown954 / 1013
• Tree Coin Collecting I230 / 253
• Tree Coin Collecting II121 / 140
• Tree Isomorphism I1025 / 1235
• Tree Isomorphism II826 / 970
• Flight Route Requests456 / 557
• Critical Cities386 / 597
• Visiting Cities641 / 849
• Graph Coloring157 / 183
• Bus Companies188 / 192
• Split into Two Paths63 / 113
• Network Renovation893 / 1193
• Forbidden Cities769 / 1007
• Creating Offices384 / 504
• New Flight Routes293 / 795

Counting Problems

• Filled Subgrid Count I391 / 433
• Filled Subgrid Count II195 / 238
• All Letter Subgrid Count I101 / 164
• All Letter Subgrid Count II90 / 104
• Border Subgrid Count I67 / 114
• Border Subgrid Count II68 / 78
• Raab Game II72 / 84
• Empty String1519 / 1853
• Permutation Inversions966 / 1066
• Counting Bishops362 / 405
• Counting Sequences620 / 665
• Grid Paths II707 / 882
• Counting Permutations835 / 946
• Grid Completion211 / 267
• Counting Reorders222 / 327
• Tournament Graph Distribution79 / 82
• Collecting Numbers Distribution82 / 85
• Functional Graph Distribution227 / 281

Additional Problems I

• Shortest Subsequence2857 / 3790
• Distinct Values Sum465 / 478
• Distinct Values Splits321 / 340
• Swap Game1949 / 2478
• Beautiful Permutation II281 / 413
• Multiplication Table6250 / 6985
• Bubble Sort Rounds I254 / 292
• Bubble Sort Rounds II142 / 167
• Nearest Campsites I113 / 130
• Nearest Campsites II113 / 121
• Advertisement4053 / 4294
• Special Substrings922 / 1010
• Counting LCM Arrays180 / 194
• Square Subsets144 / 161
• Subarray Sum Constraints190 / 203
• Water Containers Moves107 / 114
• Water Containers Queries135 / 141
• Stack Weights549 / 651
• Maximum Average Subarrays108 / 119
• Subsets with Fixed Average143 / 155
• Two Array Average136 / 153
• Pyramid Array668 / 814
• Permutation Subsequence153 / 156
• Bit Inversions2193 / 2501
• Writing Numbers702 / 759
• Letter Pair Move Game187 / 266
• Maximum Building I1960 / 2045
• Sorting Methods729 / 781
• Cyclic Array1103 / 1257
• List of Sums445 / 584

Additional Problems II

• Bouncing Ball Steps159 / 174
• Bouncing Ball Cycle63 / 87
• Knight Moves Queries86 / 103
• K Subset Sums I118 / 157
• K Subset Sums II61 / 83
• Increasing Array II742 / 858
• Food Division498 / 590
• Swap Round Sorting393 / 485
• Binary Subsequences273 / 401
• School Excursion1294 / 1374
• Coin Grid808 / 948
• Grid Coloring II91 / 114
• Programmers and Artists459 / 645
• Removing Digits II204 / 452
• Coin Arrangement306 / 413
• Replace with Difference89 / 106
• Grid Puzzle I499 / 547
• Grid Puzzle II462 / 510
• Bit Substrings361 / 440
• Reversal Sorting332 / 404
• Book Shop II1108 / 1275
• GCD Subsets296 / 303
• Minimum Cost Pairs68 / 92
• Same Sum Subsets77 / 140
• Mex Grid Queries800 / 939
• Maximum Building II423 / 518
• Stick Divisions3594 / 4223
• Stick Difference27 / 151
• Coding Company1374 / 1818
• Two Stacks Sorting160 / 506