I had applied online on my school’s career website. I got an email for a phone screen within a week.
During the phone screen, I was asked a few general HR type questions.
There was one basic math question: Two cell towers (called north tower and south tower respectively because of their obvious locations) are 8 km apart. A round trip for a message from a stationary cell phone to the north tower takes 40 microseconds and the same for the south tower is 67 microseconds. Find the approximate location of the cell phone.
Answer: Use distance=speed of light*(round trip time/2). It will be 6km from north tower and 10km from the south tower. By geometry, the cell phone is located either on the east or west at the distance of 6km from the north tower on a line perpendicular to the line joining the two towers.
It was followed by a technical test wherein I had to choose one question out of three and send the code within 24 hours. These were the questions:
1. Assume the US dollar is available in denominations of $100, $50, $20, $10, $5, $1, $0.25, $0.10, $0.05 and $0.01. Write a function to return the number of different ways to exactly represent an arbitrary value less than $1,000.00 using any number or combination of these denominations.
2. Determine the sum of all prime numbers less than an input number (the input number will be at most 10,000,000).
3. I have a csv format table of telephone calls; each call is on a line of the format “calling #, called #” (e.g., several lines similar to "123456, 222".) Define friends as any two people who have talked, and acquaintances as any two people who are not friends, but share a friend. Thus, if A talks to B, and C talks to B, then A and B are friends, A and C are acquaintances. Find who has the most acquaintances. The table will have at most 1,000,000 entries, and the phone numbers will be integers with at most 15 digits.
I got through this coding round and then there was one technical phone interview. The questions were aligned with the work done in the team I was interviewing for. The questions were on basic C programming, some algorithms, probability and testing. The testing questions were pretty vague and I could not understand what the interviewer wanted. This may have led to my reject which I got within few days.
