Challenge: Find First Unique Integer in an Array

Given an array, find the first integer, which is unique in the array. Unique means the number does not repeat and appears only once in the whole array. Implement your solution in JavaScript and see if it runs correctly!

We'll cover the following

Problem Statement
Coding Challenge

Problem Statement

Implement a function, findFirstUnique(arr), which takes an array as input and returns the first unique integer in the array.

Here you will use your knowledge of Hash Tables to write another solution of this challenge.

Note: The function should return null if no unique number is found.

Input

An array of integers

Output

The first unique element in the array

Sample Input

[9,2,3,2,6,6]

Sample Output

Level up your interview prep. Join Educative to access 70+ hands-on prep courses.

Introduction to Complexity Measures

Introduction to Arrays

Introduction to Linked Lists

Introduction to Stack/Queues

Introduction to Graphs

Introduction to Trees

Trie

Introduction to Heap

Introduction to Hashing

Summary of Data Structures