11.Container With Most Water
MediumArrayGreedyTwo Pointers60.9% acceptance57 companiesVideo
Medium · 1,169 results
15.3Sum
MediumArraySortingTwo Pointers40.1% acceptance57 companiesVideo
16.3Sum Closest
MediumArraySortingTwo Pointers47.4% acceptance11 companiesVideo
18.4Sum
MediumArraySortingTwo Pointers42.0% acceptance20 companiesVideo
31.Next Permutation
MediumArrayTwo Pointers46.1% acceptance31 companiesVideo
33.Search in Rotated Sorted Array
MediumArrayBinary Search45.5% acceptance53 companiesVideo
34.Find First and Last Position of Element in Sorted Array
MediumArrayBinary Search49.7% acceptance29 companiesVideo
36.Valid Sudoku
MediumArrayHash TableMatrix64.9% acceptance26 companiesVideo
39.Combination Sum
MediumArrayBacktracking76.9% acceptance26 companiesVideo
40.Combination Sum II
MediumArrayBacktracking60.3% acceptance15 companiesVideo
45.Jump Game II
MediumArrayDynamic ProgrammingGreedy43.2% acceptance26 companiesVideo
46.Permutations
MediumArrayBacktracking82.3% acceptance25 companiesVideo
47.Permutations II
MediumArrayBacktracking64.3% acceptance9 companiesVideo
48.Rotate Image
MediumArrayMathMatrix80.7% acceptance36 companiesVideo
49.Group Anagrams
MediumArrayHash TableSorting73.0% acceptance87 companiesVideo
53.Maximum Subarray
MediumArrayDivide and ConquerDynamic Programming53.7% acceptance64 companiesVideo
54.Spiral Matrix
MediumArrayMatrixSimulation58.2% acceptance49 companiesVideo
55.Jump Game
MediumArrayDynamic ProgrammingGreedy41.2% acceptance33 companiesVideo
56.Merge Intervals
MediumArraySorting52.6% acceptance112 companiesVideo
57.Insert Interval
MediumArray46.1% acceptance16 companiesVideo
59.Spiral Matrix II
MediumArrayMatrixSimulation76.0% acceptance11 companiesVideo
63.Unique Paths II
MediumArrayDynamic ProgrammingMatrix44.9% acceptance9 companiesVideo
64.Minimum Path Sum
MediumArrayDynamic ProgrammingMatrix68.6% acceptance17 companiesVideo
73.Set Matrix Zeroes
MediumArrayHash TableMatrix63.8% acceptance22 companiesVideo
74.Search a 2D Matrix
MediumArrayBinary SearchMatrix54.4% acceptance19 companiesVideo
75.Sort Colors
MediumArraySortingTwo Pointers69.9% acceptance37 companiesVideo
78.Subsets
MediumArrayBacktrackingBit Manipulation82.7% acceptance21 companiesVideo
79.Word Search
MediumArrayBacktrackingMatrix48.2% acceptance36 companiesVideo
80.Remove Duplicates from Sorted Array II
MediumArrayTwo Pointers65.0% acceptance9 companiesVideo
81.Search in Rotated Sorted Array II
MediumArrayBinary Search40.4% acceptance10 companiesVideo
90.Subsets II
MediumArrayBacktrackingBit Manipulation61.7% acceptance9 companiesVideo
105.Construct Binary Tree from Preorder and Inorder Traversal
MediumArrayBinary TreeDivide and Conquer69.7% acceptance9 companiesVideo
106.Construct Binary Tree from Inorder and Postorder Traversal
MediumArrayBinary TreeDivide and Conquer69.4% acceptance7 companiesVideo
120.Triangle
MediumArrayDynamic Programming59.9% acceptance11 companiesVideo
122.Best Time to Buy and Sell Stock II
MediumArrayDynamic ProgrammingGreedy71.4% acceptance28 companiesVideo
128.Longest Consecutive Sequence
MediumArrayHash TableUnion Find47.0% acceptance40 companiesVideo
130.Surrounded Regions
MediumArrayBreadth-First SearchDepth-First Search46.1% acceptance12 companiesVideo
134.Gas Station
MediumArrayGreedy48.4% acceptance29 companiesVideo
137.Single Number II
MediumArrayBit Manipulation68.0% acceptance5 companiesVideo
139.Word Break
MediumArrayDynamic ProgrammingHash Table49.8% acceptance32 companiesVideo
150.Evaluate Reverse Polish Notation
MediumArrayMathStack58.5% acceptance18 companiesVideo
152.Maximum Product Subarray
MediumArrayDynamic Programming37.3% acceptance23 companiesVideo
153.Find Minimum in Rotated Sorted Array
MediumArrayBinary Search55.3% acceptance18 companiesVideo
162.Find Peak Element
MediumArrayBinary Search46.8% acceptance30 companiesVideo
164.Maximum Gap
MediumArrayBucket SortRadix Sort53.4% acceptance7 companiesVideo
167.Two Sum II - Input Array Is Sorted
MediumArrayBinary SearchTwo Pointers66.1% acceptance16 companiesVideo
179.Largest Number
MediumArrayGreedySorting43.9% acceptance23 companiesVideo
189.Rotate Array
MediumArrayMathTwo Pointers45.3% acceptance27 companiesVideo
198.House Robber
MediumArrayDynamic Programming53.6% acceptance40 companiesVideo
200.Number of Islands
MediumArrayBreadth-First SearchDepth-First Search65.2% acceptance86 companiesVideo
Showing 1–50 of 1,169
How to use these solutions
Each solution breaks the problem into approaches, usually from brute force to the best one, and explains why each works. Code comes in Python, Java, C++ and other languages. Knowing why an approach works matters more in an interview than remembering the code.
- Try the problem first. Give it at least 20 minutes before you open the solution.
- Read every approach. The brute force shows you the problem; the faster ones show the pattern.
- Check the complexity. Note the time and space of each approach and what makes the difference.
- Write it yourself. Close the solution and code it from memory in the editor.
- Come back in a week. Solving it again later is what makes the pattern stick.