Coding Practice
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76
Problems
32
Easy
39
Medium
5
Hard
#ProblemCategoryDifficultyPriorityScore
13 SumArray & MatrixMedium—2Dot Product of Two Sparse VectorsMathMedium—3Find the Duplicate NumberArray & MatrixMedium—4LRU CacheData StructuresMedium—5Meeting Rooms IIArray & MatrixMedium—6Trap Rain WaterArray & MatrixHard—7Delete Node in a Linked ListLinked ListEasy—8Linked List CycleLinked ListEasy—9Merge Two Sorted ListsLinked ListEasy—10Read N Characters Given Read4Systems ProgrammingEasy—11Remove Duplicates from Sorted ListLinked ListEasy—12Reverse Linked ListLinked ListEasy—13strstr (Implement strStr)StringEasy—14Valid PalindromeStringEasy—15Continuous Subarray SumArray & MatrixMedium—16Decode StringStringMedium—17Decode WaysArray & MatrixMedium—18Delete Nth Node From End of Linked ListLinked ListMedium—19Exclusive Time of FunctionsSystems ProgrammingMedium—20Find All Anagrams in a StringStringMedium—21House RobberArray & MatrixMedium—22Insert Delete GetRandom O(1)Data StructuresMedium—23Maximum Product SubarrayArray & MatrixMedium—24Maximum SwapArray & MatrixMedium—25Random Pick with WeightArray & MatrixMedium—26Reorder ListLinked ListMedium—27Reverse Integer without using long longMathMedium—28Sort ColorsArray & MatrixMedium—29Task SchedulerSystems ProgrammingMedium—30Find Median from Data StreamData StructuresHard—31Convert a Number to HexadecimalBit ManipulationEasy—32Intersection of Two Linked ListsLinked ListEasy—33Middle of the Linked ListLinked ListEasy—34Number ComplementBit ManipulationEasy—35Number of 1 BitsBit ManipulationEasy—36Palindrome Linked ListLinked ListEasy—37Palindrome NumberMathEasy—38Remove Linked List ElementsLinked ListEasy—39Reverse BitsBit ManipulationEasy—40Single NumberBit ManipulationEasy—41Valid Palindrome IIStringEasy—42Best Time to Sell Stocks IIArray & MatrixMedium—43Bitwise XOR in a SubarrayBit ManipulationMedium—44Diagonal TraverseArray & MatrixMedium—45Divide Two IntegersBit ManipulationMedium—46Friends Of Appropriate AgesArray & MatrixMedium—47Pow(x, n)MathMedium—48Range Bitwise ANDBit ManipulationMedium—49Repeated DNA SequencesBit ManipulationMedium—50Reverse Linked List IILinked ListMedium—51Single Number IIBit ManipulationMedium—52Single Number IIIBit ManipulationMedium—53Sum of Two IntegersBit ManipulationMedium—54Total Hamming DistanceBit ManipulationMedium—55UTF-8 ValidationBit ManipulationMedium—56First Missing PositiveArray & MatrixHard—57LFU CacheData StructuresHard—58Read N Characters Given Read4 II (call multiple times)Systems ProgrammingHard—59Add BinaryBit ManipulationEasy—60Add StringsStringEasy—61Degree of an ArrayArray & MatrixEasy—62Hamming DistanceBit ManipulationEasy—63Is Power of FourBit ManipulationEasy—64Longest Continuous Increasing SubsequenceArray & MatrixEasy—65Missing NumberBit ManipulationEasy—66Monotonic ArrayArray & MatrixEasy—67Running Sum of 1d ArrayArray & MatrixEasy—68Sort Integers by The Number of 1 BitsBit ManipulationEasy—69Ugly NumberMathEasy—70Flatten Binary Tree to Linked ListLinked ListMedium—71Letter Case PermutationStringMedium—72Maximum Length of a Concatenated String with Unique CharactersBit ManipulationMedium—73SubsetsBit ManipulationMedium—74XOR Queries of a SubarrayBit ManipulationMedium—75Convert Binary Number in a Linked List to IntegerLinked ListEasy—76XOR Operation in an ArrayBit ManipulationEasy—