Nearest DashMart: Distance from Every Cell to the Closest Destination (Multi-Source BFS)

Also reported as LeetCode 286

Phone ScreenDoorDashLast reported July 2026Low Frequency

Reported: 3× across candidate reports
First seen: April 2026
Last reported: July 2026
Reported outcome: pass

Problem Overview

DoorDash phone-screen question, reconstructed from 3 candidate reports (April 2026 to July 2026). Candidates reported 3 follow-ups. The write-up includes a Python solution that passes 10 test cases.

3 candidate-reported follow-ups — the probes candidates report being asked, with the trigger for each
The full problem statement — full requirements, constraints, and edge cases
Approach and trade-offs — what passing candidates did, and the mistakes that sink people

Unlock the full DoorDash catalog

Full problem statements, candidate-reported follow-ups, and walkthroughs — for every DoorDash question.

Unlock with Pro

Already a member? Sign in

Verified Source

Every question is reconstructed from multiple independent candidate reports. Follow-ups candidates reported, not invented ones.

Codex Fact-Checked

Technical claims, formulas, and scale numbers are reviewed against primary sources.

Interviewer Follow-ups

The follow-ups candidates reported, with the trigger that prompts each one — plus the mistakes that sink people.