Associate Software Engineer

You are given a string 'Str' consisting of 'N' lowercase Latin letters. You have to find the longest substring of the given string without repeating characters.

String ‘B’ is a substring of string ‘A’ if it can be obtained from ‘A’ by deletion of several (possibly, zero or all) characters from the beginning and several (possibly, zero or all) characters from the end.

For Example :

If the given input string is "aabc", then you should return "abc" as the longest substring without repeating characters.

Note :

If there are multiple substrings with the same length, then you should print the substring which comes earlier in the given string. 

For Example :

If the given input string is "abcda", here “abcd” and “bcda” can be the longest unique substring but “abcd” comes earlier in the given string. So we will print “abcd” as the longest unique substring.

You are given a queue of 'N' elements. Your task is to reverse the order of elements present in the queue.

You can only use the standard operations of the QUEUE STL.

1. enqueue(x): Add an item x to the rear of the queue.

2. dequeue(): Removes an item from the front of the queue.

3. size(): Returns the number of elements in the queue.

4. front(): Finds front element.

5. empty(): Checks whether the queue is empty or not.

Given a graph with 'V' vertices numbered from 0 to 'V' - 1 and 'E' edges. Determine if it is a tree or not?

Ninja is now bored with numbers and is now playing with characters but hates when he gets repeated characters. Ninja is provided a string, and he wants to return the first unique character in the string.The string will contain characters only from the English alphabet set, i.e., ('A' - 'Z') and ('a' - 'z'). If there is no non-repeating character, print the first character of the string. If there is no non-repeating character, return the first character of the string.

Given an array 'A' consisting of 'N' integers, find the smallest subarray of 'A' containing exactly 'K' distinct integers.

Note :

If more than one such contiguous subarrays exist, consider the subarray having the smallest leftmost index.

For example - if A is [1, 2, 2, 3, 1, 3 ] and k = 2 then the subarrays: [1,2], [2,3], [3,1], [1,3] are the smallest subarrays containing 2 distinct elements. In this case, we will consider the starting and ending index of subarray [1,2] i.e. 0 and 1.

You have been given a Singly Linked List of integers, determine if it forms a cycle or not. If there is a cycle, remove the cycle and return the list.

A cycle occurs when a node's ‘next’ points back to a previous node in the list.

• How would you write a query to find employees with the same salary from an employee table?
• What is the default ordering of data using the ORDER BY clause? How could it be changed?
• Do the following query returns the output?

                SELECT subject_code, AVG (marks)  

                FROM Students  

                WHERE AVG(marks) > 70  

                GROUP BY subject_code;  

Design a cache controller