Minimum Platforms Required

MediumPython

Problem

ClearTax operates scheduled employee shuttle services between office locations. Given the arrival and departure times of buses at one station, compute the minimum number of platforms required so that no bus waits for an available platform.

You are given two arrays, arrivals and departures, where arrivals[i] and departures[i] represent the arrival and departure time of the same bus. Times are integers in HHMM format, such as 930 for 9:30 AM and 1545 for 3:45 PM. A platform remains occupied when a bus arrives at exactly the same time another bus departs.

Return the minimum number of platforms needed at any point during the schedule.

Formal Specification

Implement min_platforms(arrivals, departures).

Input: Two integer arrays of equal length, with each departure occurring after its corresponding arrival.
Output: An integer representing the maximum number of buses simultaneously requiring platforms.

Constraints

1 <= len(arrivals) == len(departures) <= 10^5
0 <= arrivals[i], departures[i] <= 2359
Each bus's departure time is later than its arrival time
Times are valid HHMM values

Function Signature

def min_platforms(arrivals, departures):

Return the minimum number of platforms needed at any point during the schedule.

Formal Specification

Implement min_platforms(arrivals, departures).

Input: Two integer arrays of equal length, with each departure occurring after its corresponding arrival.
Output: An integer representing the maximum number of buses simultaneously requiring platforms.