Instacart Online Assessment Questions

Interview Experience at Instacart Toronto : Seeking Clearer Feedback After a Positive Process

I recently completed the interview process at Instacart (Toronto), starting with an online assessment, followed by a recruiter call, two coding rounds, a system design round, and a behavioral intervie

#1701 Average Waiting Time

LeetCode #1701: Average Waiting Time. Difficulty: Medium. Topics: Array, Simulation. Asked at Instacart in the last 6 months.

#34 Find First and Last Position of Element in Sorted Array

LeetCode #34: Find First and Last Position of Element in Sorted Array. Difficulty: Medium. Topics: Array, Binary Search. Asked at Instacart in the last 6 months.

#49 Group Anagrams

LeetCode #49: Group Anagrams. Difficulty: Medium. Topics: Array, Hash Table, String, Sorting. Asked at Instacart in the last 6 months.

Design an In-Memory Database with Field-Level TTL, Prefix Scan, and Backup/Restore

Design and implement an **in-memory database** keyed by `key` (unique per record). Each record contains multiple `field -> value` pairs, where both `field` and `value` are strings. Implement the foll

Count Subarrays With Alternating Parity (Odd/Even) Including Negatives

Given an integer array `nums` (may contain negative numbers), count how many **contiguous subarrays** have strictly alternating parity between adjacent elements. Formally, a subarray `nums[l..r]` is

Flip Inner Segment If String Starts and Ends With Vowels

Given an array of strings `arr`, transform each string `s` as follows and return the resulting array: - If both the first and last characters of `s` are vowels, reverse (mirror) the inner substring o

Compute counts on nested maps (Level 1/Level 2 aggregation)

You are given a data structure consisting of nested maps (dictionaries/JSON objects). The data has the notion of “Level 1” and “Level 2” (corresponding to two specific nesting layers). Compute and ou

Bus Boarding Simulation (Priority + Wheelchair Capacity)

Implement a bus boarding simulator with regular riders, priority boarding, and wheelchair constraints. Design and implement functions/classes to support the following (progressive) requirements: ##

Evaluate an Arithmetic Expression

Given a string `expr` representing an arithmetic expression, evaluate it. **Rules** - `expr` contains non-negative integers, operators `+ - * /`, parentheses `(` `)`, and spaces. - Operator precedenc