Third Round (Technical Round-2)
The interviewer was very kind and helpful. This round started with the questions from my online test, so I explained them all. Then he asked about GitHub commands, as I had mentioned GitHub in my resume. After that, he asked about my project, like why I used MongoDB, why I did not use an SQL database, and the difference between SQL and NoSQL databases. Then he asked me two DSA problems based on arrays and strings.
- I am given an unsorted array consisting of positive and negative integers. I have to find the first missing positive integer from this array.
- Given a string “AABCDACD”, return the string that consists of the first non-repeating character corresponding to each character in the given string. For example, given str =”ABCDAABC”, the output should be “AAAABBCD”. For i=0, the first non-repeating character is A. For i=1, ‘B’ is also unique, so the first non-repeating character is also A. For C, return A. For D, return A. But for i=3, ‘A’ is now repeated, so ‘B’ will be the first non-repeating character.