Visa Inc. Software Engineer(Internship) interview questions

I joined the call with the HR who was supposed to interview me. Then we had the call for nearly an hour. The interview was primarily intended to test my computer science core subjects knowledge and at the same time focusing on my problem solving skills. He asked me question on Operating System concepts, Databases, System Design, DSA, Computer Networks etc.

2 medium (string, arrays) and 1 dictionary (hard problem). all leetcode level questions. Interview was in hacker rank with camera on. The Challenge: Design a data structure to store the strings' count with the ability to return the strings with minimum and maximum counts. Implement a class that increments a string's count, decrements a string's count, gets the key with the maximum count, and gets the key with the minimum count—all in \(O(1)\) time complexity.