CSES Problem Set

General

• Introduction
• Create new account
• Statistics

Introductory Problems

• Weird Algorithm143092 / 149857
• Missing Number123186 / 129269
• Repetitions107466 / 111929
• Increasing Array100866 / 104590
• Permutations88758 / 91539
• Number Spiral62743 / 68426
• Two Knights47843 / 49393
• Two Sets52035 / 56082
• Bit Strings59717 / 63071
• Trailing Zeros55761 / 59357
• Coin Piles49360 / 54068
• Palindrome Reorder45727 / 48325
• Gray Code30351 / 34197
• Tower of Hanoi28034 / 29159
• Creating Strings38658 / 39680
• Apple Division38592 / 43716
• Chessboard and Queens23273 / 23706
• Raab Game I2817 / 3223
• Mex Grid Construction2668 / 2855
• Knight Moves Grid2718 / 2770
• Grid Coloring I2216 / 2293
• Digit Queries16430 / 19252
• String Reorder2246 / 2601
• Grid Path Description9210 / 11995

Sorting and Searching

• Distinct Numbers69631 / 75437
• Apartments51608 / 57536
• Ferris Wheel49492 / 53561
• Concert Tickets39880 / 46591
• Restaurant Customers40664 / 43962
• Movie Festival38988 / 41345
• Sum of Two Values45465 / 51058
• Maximum Subarray Sum44160 / 46176
• Stick Lengths39399 / 41280
• Missing Coin Sum29480 / 30588
• Collecting Numbers30207 / 32411
• Collecting Numbers II12428 / 16008
• Playlist30267 / 34756
• Towers30668 / 32912
• Traffic Lights23684 / 26600
• Distinct Values Subarrays4124 / 4326
• Distinct Values Subsequences2858 / 3209
• Josephus Problem I17957 / 19896
• Josephus Problem II9686 / 13370
• Nested Ranges Check10252 / 11853
• Nested Ranges Count6972 / 8246
• Room Allocation17849 / 20562
• Factory Machines25205 / 27576
• Tasks and Deadlines20442 / 20890
• Reading Books16572 / 17757
• Sum of Three Values24250 / 26943
• Sum of Four Values15108 / 16927
• Nearest Smaller Values20253 / 20950
• Subarray Sums I26692 / 28548
• Subarray Sums II24064 / 28765
• Subarray Divisibility22177 / 24254
• Distinct Values Subarrays II13037 / 14478
• Array Division20959 / 22090
• Movie Festival II11124 / 13480
• Maximum Subarray Sum II10286 / 12362

Dynamic Programming

• Dice Combinations72808 / 77121
• Minimizing Coins62909 / 67679
• Coin Combinations I57478 / 62330
• Coin Combinations II48606 / 55158
• Removing Digits54232 / 55368
• Grid Paths I50908 / 52386
• Book Shop45447 / 50138
• Array Description33399 / 37227
• Counting Towers20163 / 21396
• Edit Distance33676 / 35572
• Longest Common Subsequence5721 / 5960
• Rectangle Cutting28011 / 30620
• Minimal Grid Path2424 / 4728
• Money Sums33220 / 34531
• Removal Game19308 / 26553
• Two Sets II26192 / 28274
• Mountain Range1675 / 3276
• Increasing Subsequence26764 / 30082
• Projects18388 / 20649
• Elevator Rides11592 / 14691
• Counting Tilings6749 / 7390
• Counting Numbers9128 / 10370
• Increasing Subsequence II3325 / 3850

Graph Algorithms

• Counting Rooms49964 / 52576
• Labyrinth34453 / 41538
• Building Roads43714 / 45322
• Message Route37491 / 39041
• Building Teams35380 / 37402
• Round Trip28082 / 30687
• Monsters18970 / 22585
• Shortest Routes I30527 / 33879
• Shortest Routes II24901 / 28045
• High Score14908 / 21523
• Flight Discount19481 / 22956
• Cycle Finding13830 / 17138
• Flight Routes13471 / 15068
• Round Trip II15462 / 17441
• Course Schedule20316 / 21544
• Longest Flight Route14110 / 17765
• Game Routes15962 / 17169
• Investigation11812 / 12739
• Planets Queries I10200 / 12029
• Planets Queries II3658 / 4653
• Planets Cycles6303 / 7063
• Road Reparation15507 / 16180
• Road Construction17036 / 17592
• Flight Routes Check13833 / 15051
• Planets and Kingdoms11094 / 11499
• Giant Pizza4524 / 5001
• Coin Collector7160 / 7988
• Mail Delivery6004 / 6595
• De Bruijn Sequence3120 / 3272
• Teleporters Path4505 / 5213
• Hamiltonian Flights6780 / 7763
• Knight's Tour2516 / 3074
• Download Speed4453 / 6068
• Police Chase3566 / 4027
• School Dance3954 / 4194
• Distinct Routes2705 / 3585

Range Queries

• Static Range Sum Queries34320 / 35877
• Static Range Minimum Queries24212 / 25968
• Dynamic Range Sum Queries25200 / 26346
• Dynamic Range Minimum Queries22835 / 23391
• Range Xor Queries23614 / 23936
• Range Update Queries18615 / 20013
• Forest Queries19034 / 19772
• Hotel Queries13409 / 14292
• List Removals11171 / 11782
• Salary Queries8210 / 10490
• Prefix Sum Queries7042 / 7658
• Pizzeria Queries5689 / 5918
• Visible Buildings Queries925 / 1016
• Range Interval Queries734 / 964
• Subarray Sum Queries6894 / 7514
• Subarray Sum Queries II993 / 1026
• Distinct Values Queries6278 / 7838
• Distinct Values Queries II580 / 671
• Increasing Array Queries2427 / 2789
• Movie Festival Queries1141 / 1270
• Forest Queries II4162 / 4489
• Range Updates and Sums5484 / 6566
• Polynomial Queries4054 / 4767
• Range Queries and Copies2883 / 3102
• Missing Coin Sum Queries558 / 742

Tree Algorithms

• Subordinates28821 / 30865
• Tree Matching16314 / 19078
• Tree Diameter23470 / 24926
• Tree Distances I17804 / 19191
• Tree Distances II14656 / 15289
• Company Queries I16239 / 17118
• Company Queries II15214 / 15978
• Distance Queries13869 / 14908
• Counting Paths8608 / 9155
• Subtree Queries10367 / 11081
• Path Queries8250 / 8750
• Path Queries II3292 / 4999
• Distinct Colors7990 / 8851
• Finding a Centroid6448 / 6727
• Fixed-Length Paths I3028 / 3970
• Fixed-Length Paths II1405 / 2634

Mathematics

• Josephus Queries4366 / 5506
• Exponentiation22746 / 24313
• Exponentiation II16131 / 19413
• Counting Divisors20613 / 23324
• Common Divisors13547 / 15808
• Sum of Divisors7526 / 11401
• Divisor Analysis5123 / 6900
• Prime Multiples5812 / 6836
• Counting Coprime Pairs3797 / 4462
• Next Prime1132 / 1293
• Binomial Coefficients9520 / 10598
• Creating Strings II8032 / 8501
• Distributing Apples7738 / 8338
• Christmas Party6190 / 6664
• Permutation Order527 / 536
• Permutation Rounds579 / 645
• Bracket Sequences I4261 / 4651
• Bracket Sequences II2213 / 2550
• Counting Necklaces2042 / 2218
• Counting Grids1657 / 1773
• Fibonacci Numbers6600 / 8323
• Throwing Dice3416 / 3721
• Graph Paths I3249 / 3490
• Graph Paths II2711 / 2843
• System of Linear Equations260 / 281
• Sum of Four Squares402 / 470
• Triangle Number Sums344 / 429
• Dice Probability2948 / 3185
• Moving Robots1512 / 1602
• Candy Lottery1212 / 2780
• Inversion Probability415 / 2137
• Stick Game3273 / 3351
• Nim Game I4331 / 4496
• Nim Game II3433 / 3585
• Stair Game2323 / 2529
• Grundy's Game1586 / 2096
• Another Game1800 / 1945

String Algorithms

• Word Combinations5483 / 8020
• String Matching10705 / 14446
• Finding Borders7830 / 8580
• Finding Periods5584 / 6354
• Minimal Rotation2710 / 4183
• Longest Palindrome4099 / 5447
• All Palindromes383 / 434
• Required Substring1542 / 2398
• Palindrome Queries1930 / 2257
• Finding Patterns1776 / 2554
• Counting Patterns1676 / 2095
• Pattern Positions1404 / 1721
• Distinct Substrings1604 / 1920
• Distinct Subsequences994 / 1061
• Repeating Substring1726 / 2027
• String Functions1517 / 1592
• Inverse Suffix Array135 / 153
• String Transform483 / 593
• Substring Order I1087 / 1225
• Substring Order II718 / 931
• Substring Distribution1012 / 1103

Geometry

• Point Location Test6807 / 7623
• Line Segment Intersection4058 / 5138
• Polygon Area4739 / 5034
• Point in Polygon2582 / 3288
• Polygon Lattice Points2186 / 2267
• Minimum Euclidean Distance1895 / 2647
• Convex Hull3103 / 3763
• Maximum Manhattan Distances354 / 363
• All Manhattan Distances368 / 402
• Intersection Points1837 / 1980
• Line Segments Trace I201 / 206
• Line Segments Trace II159 / 168
• Lines and Queries I215 / 223
• Lines and Queries II186 / 193
• Area of Rectangles1035 / 1157
• Robot Path288 / 499

Advanced Techniques

• Meet in the Middle6273 / 8845
• Hamming Distance3076 / 3352
• Corner Subgrid Check219 / 319
• Corner Subgrid Count2145 / 2403
• Reachable Nodes2120 / 2287
• Reachability Queries1416 / 1681
• Cut and Paste1420 / 1582
• Substring Reversals1243 / 1359
• Reversals and Sums1253 / 1355
• Necessary Roads1823 / 1867
• Necessary Cities1700 / 1785
• Eulerian Subgraphs747 / 788
• Monster Game I1080 / 1205
• Monster Game II960 / 1033
• Subarray Squares1264 / 1511
• Houses and Schools711 / 851
• Knuth Division855 / 971
• Apples and Bananas941 / 1025
• One Bit Positions768 / 844
• Signal Processing709 / 765
• New Roads Queries2022 / 2472
• Dynamic Connectivity906 / 1030
• Parcel Delivery695 / 777
• Task Assignment815 / 867
• Distinct Routes II533 / 616

Sliding Window Problems

• Sliding Window Sum2842 / 2982
• Sliding Window Minimum2202 / 2529
• Sliding Window Xor2147 / 2174
• Sliding Window Or903 / 1666
• Sliding Window Distinct Values1792 / 1830
• Sliding Window Mode1259 / 1321
• Sliding Window Mex1128 / 1191
• Sliding Window Median12913 / 14790
• Sliding Window Cost8598 / 9933
• Sliding Window Inversions659 / 701
• Sliding Window Advertisement124 / 196

Interactive Problems

• Hidden Integer1224 / 1262
• Hidden Permutation541 / 639
• K-th Highest Score224 / 271
• Permuted Binary Strings317 / 325
• Colored Chairs263 / 277
• Inversion Sorting160 / 169

Bitwise Operations

• Counting Bits4115 / 5294
• Maximum Xor Subarray2542 / 2833
• Maximum Xor Subset542 / 587
• Number of Subset Xors463 / 475
• K Subset Xors226 / 266
• All Subarray Xors167 / 247
• Xor Pyramid Peak1749 / 2155
• Xor Pyramid Diagonal184 / 209
• Xor Pyramid Row153 / 174
• SOS Bit Problem1800 / 1924
• And Subset Count225 / 230

Construction Problems

• Inverse Inversions1265 / 1340
• Monotone Subsequences766 / 899
• Third Permutation226 / 260
• Permutation Prime Sums221 / 239
• Chess Tournament1063 / 1226
• Distinct Sums Grid62 / 106
• Filling Trominos220 / 377
• Grid Path Construction110 / 408

Advanced Graph Problems

• Nearest Shops420 / 548
• Prüfer Code1372 / 1486
• Tree Traversals1078 / 1190
• Course Schedule II1680 / 2417
• Acyclic Graph Edges2036 / 2163
• Strongly Connected Edges1403 / 1557
• Even Outdegree Edges1209 / 1425
• Graph Girth3076 / 3531
• Fixed Length Walk Queries221 / 236
• Transfer Speeds Sum247 / 253
• MST Edge Check318 / 343
• MST Edge Set Check131 / 148
• MST Edge Cost228 / 240
• Network Breakdown907 / 962
• Tree Coin Collecting I186 / 204
• Tree Coin Collecting II100 / 116
• Tree Isomorphism I990 / 1187
• Tree Isomorphism II803 / 946
• Flight Route Requests434 / 529
• Critical Cities379 / 579
• Visiting Cities622 / 826
• Graph Coloring121 / 146
• Bus Companies160 / 163
• Split into Two Paths55 / 98
• Network Renovation867 / 1155
• Forbidden Cities736 / 974
• Creating Offices380 / 493
• New Flight Routes282 / 758

Counting Problems

• Filled Subgrid Count I307 / 343
• Filled Subgrid Count II158 / 191
• All Letter Subgrid Count I75 / 126
• All Letter Subgrid Count II62 / 73
• Border Subgrid Count I55 / 98
• Border Subgrid Count II59 / 69
• Raab Game II57 / 68
• Empty String1463 / 1786
• Permutation Inversions924 / 1015
• Counting Bishops352 / 394
• Counting Sequences597 / 643
• Grid Paths II694 / 864
• Counting Permutations809 / 917
• Grid Completion199 / 254
• Counting Reorders209 / 305
• Tournament Graph Distribution63 / 65
• Collecting Numbers Distribution69 / 71
• Functional Graph Distribution217 / 273

Additional Problems I

• Shortest Subsequence2793 / 3715
• Distinct Values Sum358 / 368
• Distinct Values Splits253 / 269
• Swap Game1884 / 2393
• Beautiful Permutation II173 / 243
• Multiplication Table5978 / 6693
• Bubble Sort Rounds I193 / 225
• Bubble Sort Rounds II100 / 117
• Nearest Campsites I92 / 106
• Nearest Campsites II88 / 99
• Advertisement3949 / 4185
• Special Substrings900 / 985
• Counting LCM Arrays150 / 161
• Square Subsets121 / 137
• Subarray Sum Constraints125 / 136
• Water Containers Moves81 / 90
• Water Containers Queries117 / 121
• Stack Weights533 / 633
• Maximum Average Subarrays87 / 95
• Subsets with Fixed Average114 / 123
• Two Array Average106 / 120
• Pyramid Array653 / 792
• Permutation Subsequence131 / 133
• Bit Inversions2137 / 2446
• Writing Numbers688 / 745
• Letter Pair Move Game177 / 257
• Maximum Building I1923 / 2008
• Sorting Methods716 / 767
• Cyclic Array1063 / 1212
• List of Sums430 / 561

Additional Problems II

• Bouncing Ball Steps133 / 144
• Bouncing Ball Cycle52 / 71
• Knight Moves Queries77 / 90
• K Subset Sums I92 / 129
• K Subset Sums II51 / 69
• Increasing Array II732 / 845
• Food Division487 / 576
• Swap Round Sorting386 / 477
• Binary Subsequences263 / 390
• School Excursion1248 / 1328
• Coin Grid769 / 907
• Grid Coloring II78 / 100
• Programmers and Artists473 / 624
• Removing Digits II193 / 441
• Coin Arrangement293 / 399
• Replace with Difference64 / 80
• Grid Puzzle I476 / 523
• Grid Puzzle II425 / 469
• Bit Substrings344 / 422
• Reversal Sorting321 / 393
• Book Shop II1070 / 1232
• GCD Subsets241 / 247
• Minimum Cost Pairs54 / 73
• Same Sum Subsets64 / 116
• Mex Grid Queries782 / 921
• Maximum Building II409 / 504
• Stick Divisions3526 / 4145
• Stick Difference21 / 128
• Coding Company1328 / 1760
• Two Stacks Sorting153 / 481