Deloitte

Multinational professional services network with offices in over 150 countries.

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

All Roles Backend Engineer 5 Cloud Engineer 3 Data Engineer 1 Data Scientist 1 Frontend Engineer 9 Full Stack Engineer 8 Machine Learning Engineer 3 Product Manager 1 Software Engineer 8

All Topics System Design 43 Algorithms 39 SQL 21 Culture Fit 19 Adaptability 10 Security 9 CI/CD 8 Machine Learning 8

Backend Engineer • Coding • easy

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

#Strings #Stack

Practice

Backend 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, and you may not use the same element twice.

#Arrays #Hash Map

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 integer array nums and an integer k, return the k most frequent elements. You may return the answer in any order.

#Hash Map #Heap #Bucket Sort

Practice

Backend 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

Cloud Engineer • Coding • easy

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

#Strings #Stacks

Practice

Cloud Engineer • Coding • medium

Write a function to merge overlapping intervals. This is useful for processing overlapping log timeframes.

#Arrays #Sorting

Practice

Cloud Engineer • Coding • easy

Given an array of integers, return indices of the two numbers such that they add up to a specific target.

#Arrays #Hash Maps

Practice

Data Engineer • Coding • easy

Write a Python function to merge two sorted lists of integers into a single sorted list without using the built-in sort() or sorted() functions.

#Two Pointers #Arrays

Practice

Data Scientist • Coding • easy

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

#Hash Maps #Arrays #Optimization

Practice

Frontend Engineer • Coding • medium

Write a JavaScript function to flatten a deeply nested object, which is a common requirement when mapping complex client API responses to flat UI tables.

#Recursion #Data Structures #JavaScript

Practice

Frontend Engineer • Coding • easy

Given an array of integers, write a function to move all zeros to the end of it while maintaining the relative order of the non-zero elements. Do this in-place.

#Arrays #Two Pointers

Practice

Frontend Engineer • Coding • easy

Write a function that takes a string containing brackets `()`, `{}`, `[]` and determines if the input string is valid.

#Stacks #String Manipulation

Practice

Frontend Engineer • Coding • medium

Implement an infinite scroll component in React. How do you handle performance when the list reaches 10,000 items?

#React #Intersection Observer #Virtualization

Practice

Frontend Engineer • Coding • hard

Write a JavaScript function to deep clone an object, ensuring that circular references do not cause a stack overflow.

#JavaScript #Recursion #Memory Management

Practice

Frontend Engineer • Coding • medium

Implement an LRU (Least Recently Used) Cache class in JavaScript.

#Data Structures #Caching #JavaScript

Practice

Frontend Engineer • Coding • hard

Write a function to check if two DOM trees are identical structurally and have the same text content.

#DOM #Recursion #Tree Traversal

Practice

Frontend Engineer • Coding • medium

Write a custom React hook `useDebounce` that delays invoking a function until after wait milliseconds have elapsed since the last time the debounced function was invoked. How would you use this for a client's global search bar?

#JavaScript #React Hooks #Performance

Practice

Frontend Engineer • Coding • hard

Implement a polyfill for Promise.all().

#Asynchronous JavaScript #Promises #Polyfills

Practice

Full Stack Engineer • Coding • easy

Given the head of a singly linked list, reverse the list, and return the reversed list.

#Linked List #Pointers

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.

#Arrays #Hash Map

Practice

Full Stack Engineer • Coding • easy