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JavaScript Map Coding Practice Problems
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JavaScript Map Coding Practice Problems

Last Updated : 24 Feb, 2025
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Maps are an essential data structure used for storing key-value pairs. They provide efficient lookups, insertions, and deletions, and are widely used for implementing dictionaries, caches, and many other applications. This curated list of JavaScript Map Coding Practice Problems will help you master map operations. Whether you're a beginner or an experienced developer, these problems will enhance your map manipulation skills and problem-solving abilities.

Map Practice Problems

Easy

  • String Reversal
  • Map Operations
  • Parties and seats
  • Unique Number of Occurrences
  • Twice Counter
  • Frequency Game
  • Powerfull Integer
  • Balloon Everywhere
  • Sum of f(a[i], a[j]) over all pairs in an array of n integers
  • Word with maximum frequency
  • Duplicate Elements
  • Earthquake and the Paint Shop 
  • Multimap Operations
  • Distinct Substrings
  • Maximum difference Indexes
  • Greater and Smaller Ones
  • Pair Sum Existence- Revisited
  • Design HashMap

Medium

  • Longest Subarray with Sum K
  • Subarray with 0 sum
  • Longest Substring with K Uniques
  • Sort Elements by Decreasing Frequency
  • Top k numbers in a stream
  • Fraction pairs with sum 1
  • Transform String
  • Smaller on Left
  • Count distinct pairs with difference k
  • Check if a string is repetition of its substring of k-length
  • Minimize the Difference
  • Count Subarrays with given XOR
  • Maximize the sum of selected numbers from a sorted array to make it empty
  • Distinct Difference
  • Concatenate Equal to Target
  • 4 Sum – Count quadruplets with given sum
  • Maximum score from at most K jumps
  • Smallest distinct window
  • Overlapping Intervals
  • Print Anagrams Together
  • Closest Three Sum
  • Nuts and Bolts Problem

Hard

  • Phone directory
  • Median of the Subarrays
  • Interesting Queries
  • Account Merge
  • Largest rectangular sub-matrix whose sum is 0
  • LFU cache
  • Smallest window containing all characters of another string
  • Minimum operations to convert array A to B
  • LRU Cache
  • Joey doesn't share food

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JavaScript Map Coding Practice Problems

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Article Tags :
  • JavaScript
  • Web Technologies
  • JavaScript-DSA
  • JavaScript-Questions
  • JavaScript-Quiz

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