Software Engineer

Given two strings, 'S' and 'T' with lengths 'M' and 'N', find the length of the 'Longest Common Subsequence'.

For a string 'str'(per se) of length K, the subsequences are the strings containing characters in the same relative order as they are present in 'str,' but not necessarily contiguous. Subsequences contain all the strings of length varying from 0 to K.

Example :

Subsequences of string "abc" are:  ""(empty string), a, b, c, ab, bc, ac, abc.

Ninja has two strings ‘s’ and ‘t’ of same length, he knows that both strings are equivalent strings which means s[i], t[i] will follow all rules of any equivalence relation that are:

Reflexive : s[i] = t[i]

Symmetric: s[i] = t[i] => t[i] = s[i]

Transitive: if s[i] = t[i] and t[i] = s[j] then s[i] = s[j]

Ninja wants your help to find the lexicographically smallest equivalent string of a given string ‘str’.

Note:

1. String ‘s’, ‘t’ and ‘str’ consist of only lowercase English letters from ‘a’ – ‘z’.
2. String ‘s’ and ‘t’ are of same length.

For example:

Let s = “abc” , t = “xyz” and str = “xbc” then all strings that we can generate are “abc”, “abz”, “ayc”,”ayz”, “xbc”, “xbz”, “xyc”, “xyz” and smallest of all these is “abc”. 

You are given a Binary Tree.

Return the length of the diameter of the tree.

Note :

The diameter of a binary tree is the length of the longest path between any two end nodes in a tree.

The number of edges between two nodes represents the length of the path between them.

Example :

Input: Consider the given binary tree:

Output: 6

Explanation:
Nodes in the diameter are highlighted. The length of the diameter, i.e., the path length, is 6.

Asked the High-Level and Low-Level design for the project I was currently working on and asked few use cases where the design can be optimized.

Asked subjective questions:
Difference between Mutex and Semaphore
Write some code to explain the Critical Section problem
Difference between Interface and Abstract classes
Write code to explain Banker's Algorithm
Asked few SQL queries for Joins, Update, Insert, Upsert, Delete, etc.