Practice problem
Step Functions
By Liza Sulkin
There are three post offices in your area. You need to get your fingerprints taken, a process notorious for its lengthy waiting time.
Post Office has a waiting time of minutes per person in line.
Post Office has a waiting time of minutes per person in line, but they don't open for another half hour.
Post Office has a waiting time of minutes per person in line for up to people, then minutes per person for each extra person in line.
If there are people in line at each post office, which one will have the shortest wait time?