EY

EY

Ernst & Young Global Limited, a multinational professional services partnership.

4 Rounds ~21 Days Medium
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The Interview Loop

Recruiter Screen (30 min)

Standard fit check, behavioral questions, and resume overview.

Technical Loop (3-4 Rounds)

Deep dive into domain knowledge, coding, and system design.

Interview Question Bank

Backend Engineer • Coding • medium

Find the Kth largest element in an unsorted array. Note that it is the kth largest element in the sorted order, not the kth distinct element.

#Arrays #Heap #Divide and Conquer
Practice
Backend Engineer • Coding • medium

Given an array of intervals where intervals[i] = [starti, endi], merge all overlapping intervals. We use this logic to consolidate billable hours or tax periods.

#Arrays #Sorting
Practice
Backend Engineer • Coding • easy

Given an array of integers and an integer target, return indices of the two numbers such that they add up to target. Assume exactly one solution exists.

#Arrays #Hash Table
Practice
Backend Engineer • Coding • easy

Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid. This is often used in our tax formula parsing engines.

#Strings #Stack
Practice
Backend Engineer • Coding • medium

Given a string s, find the length of the longest substring without repeating characters.

#Strings #Sliding Window #Hash Table
Practice
Backend Engineer • Coding • medium

Given a binary search tree (BST), find the lowest common ancestor (LCA) node of two given nodes in the BST.

#Trees #Binary Search Tree #Recursion
Practice
Backend Engineer • Coding • medium

Given an array of strings, group the anagrams together. You can return the answer in any order.

#Strings #Hash Table #Sorting
Practice
Backend Engineer • Coding • easy

Write a function to reverse a singly linked list.

#Linked Lists #Pointers
Practice
Cloud Engineer • Coding • easy

Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.

#Data Structures #Stacks
Practice
Data Scientist • Coding • medium

Write a Python script to find the Kth largest transaction amount in an unsorted array of millions of transactions.

#Heaps #Sorting #Optimization
Practice
Data Scientist • Coding • easy

Given an array of transaction amounts and a target fraudulent sum, write a function to return the indices of the two transactions that add up exactly to the target sum.

#Arrays #Hash Maps #Time Complexity
Practice
Data Scientist • Coding • easy

Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid. This is useful for parsing nested JSON logs from Azure.

#Stacks #String Parsing
Practice
Data Scientist • Coding • medium

Given a list of intervals representing meeting times, write a function to merge all overlapping intervals. This is useful for calculating continuous billable periods.

#Arrays #Sorting #Intervals
Practice
Data Scientist • Coding • easy

Given a dataset of historical stock prices, write a Python algorithm to calculate the maximum profit you could achieve from a single buy and a single sell transaction.

#Arrays #Dynamic Programming #Optimization
Practice
Data Scientist • Coding • hard

Write a Python function to calculate the TF-IDF scores for a corpus of documents from scratch (without using scikit-learn).

#NLP #Math #Python
Practice
Frontend Engineer • Coding • easy

Write a JavaScript function to flatten a deeply nested array of varying depths without using the built-in `Array.prototype.flat()`.

#Recursion #Arrays #JavaScript
Practice
Frontend Engineer • Coding • hard

Write a function to deep clone a JavaScript object. Ensure it handles circular references.

#Recursion #Memory Management #JavaScript Core
Practice
Frontend Engineer • Coding • easy

Write a function to check if two strings are valid anagrams of each other.

#Strings #Hash Maps #Algorithms
Practice
Full Stack Engineer • Coding • medium

Given an m x n 2D binary grid grid which represents a map of '1's (land) and '0's (water), return the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically.

#Graphs #DFS #BFS
Practice
Full Stack Engineer • Coding • easy

Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target. You may assume that each input would have exactly one solution.

#Arrays #Hash Maps
Practice
Full Stack Engineer • Coding • easy

Given a string s containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.

#Strings #Stacks
Practice
Full Stack Engineer • Coding • medium

Given a binary search tree (BST), find the lowest common ancestor (LCA) node of two given nodes in the BST.

#Trees #Recursion
Practice
Full Stack Engineer • Coding • medium

Given an array of intervals where intervals[i] = [starti, endi], merge all overlapping intervals, and return an array of the non-overlapping intervals that cover all the intervals in the input.

#Arrays #Sorting
Practice
Full Stack Engineer • Coding • medium

Given a string s, find the length of the longest substring without repeating characters.

#Strings #Sliding Window #Hash Maps
Practice
Machine Learning Engineer • Coding • medium

Given a string s, find the length of the longest substring without repeating characters.

#Sliding Window #Strings #Hash Table
Practice
Machine Learning Engineer • Coding • easy

Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target. You may assume that each input would have exactly one solution.

#Arrays #Hash Table
Practice
Machine Learning Engineer • Coding • easy

Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.

#Stacks #Strings
Practice
Machine Learning Engineer • Coding • hard

Write a Python function to compute the TF-IDF scores for a given corpus of financial documents from scratch, without using Scikit-learn.

#NLP #Math #Python
Practice
Machine Learning Engineer • Coding • medium

Given an array of intervals where intervals[i] = [starti, endi], merge all overlapping intervals, and return an array of the non-overlapping intervals that cover all the intervals in the input.

#Arrays #Sorting
Practice
Software Engineer • Coding • medium

Write a function to group an array of strings into anagrams. We sometimes use similar logic for fuzzy matching client names.

#Hash Table #Strings #Sorting
Practice
Software Engineer • Coding • medium

Given an array of audit engagement time intervals where intervals[i] = [start_i, end_i], merge all overlapping intervals.

#Arrays #Sorting
Practice
Software Engineer • Coding • medium

Given a string s and a dictionary of strings wordDict, return true if s can be segmented into a space-separated sequence of one or more dictionary words. Used for parsing continuous text in legacy financial documents.

#Dynamic Programming #Memoization #Trie
Practice
Software Engineer • Coding • easy

Given an array of transaction amounts and a target audit sum, return indices of the two numbers such that they add up to the target.

#Arrays #Hash Table
Practice
Software Engineer • Coding • medium

Given a string of log data, find the length of the longest substring without repeating characters.

#Sliding Window #Hash Table #Strings
Practice
Software Engineer • Coding • easy

Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid. This is often used to validate nested JSON structures in our tax APIs.

#Stacks #String Manipulation
Practice
Software Engineer • Coding • easy

Given an array containing n distinct numbers taken from 0, 1, 2, ..., n representing sequential invoice numbers, find the one that is missing from the array.

#Math #Bit Manipulation #Arrays
Practice
Software Engineer • Coding • medium

Given a binary search tree representing an organizational hierarchy, find the lowest common ancestor (LCA) node of two given employee nodes.

#Trees #Binary Search Tree #Recursion
Practice
Software Engineer • Coding • medium

Given an integer array of expense category IDs and an integer k, return the k most frequent elements.

#Heaps #Hash Table #Bucket Sort
Practice
Software Engineer • Coding • easy

Given the head of a singly linked list representing a sequence of approval workflows, reverse the list and return the reversed list.

#Linked Lists
Practice

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Senior Engineer

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