Karat Software Engineer Interview Experience — Password Validator and a Three-Table Join Over Bad Audio

Weird screen, hard to categorize, but I hope this gets seen anyway...

Classic low-quality Amazon-customer-service-tier microphone. I've worked with people like this for years and I still only understood about 50% of what the interviewer said. Fortunately they noticed too, so I politely asked them to speak a bit slower, and it got a lot better after that.

Right at the start they said I didn't need to finish every question. There was only one code pad, I wrote it in Java, and ran everything straight off main.

First question: the input is a password, and you need to determine whether it's valid and list which rules it violates.

• Length greater than 15
• Cannot contain "password" (case-insensitive)
• Must have at least one uppercase and one lowercase letter
• Must contain at least one of three special symbols
• The same character cannot appear more than four times

Second question: three tables, each given as a 2D string array. You need to match and join them.

• Customer table: name, email, product name, quantity purchased (each user only buys one type of product)
• Order table: user id, email, order total amount (email can be null)
• Product table: product name, unit price

You need to find the mapping from user id to name.

The interviewer was useless beyond just handing me the questions.