SDE - 1

The city of Ninjaland is analogous to the unweighted graph. The city has ‘N’ houses numbered from 1 to ‘N’ respectively and are connected by M bidirectional roads. If a road is connecting two houses ‘X’ and ‘Y’ which means you can go from ‘X’ to ‘Y’ or ‘Y’ to ‘X’. It is guaranteed that you can reach any house from any other house via some combination of roads. Two houses are directly connected by at max one road.

A path between house ‘S’ to house ‘T’ is defined as a sequence of vertices from ‘S’ to ‘T’. Where starting house is ‘S’ and the ending house is ‘T’ and there is a road connecting two consecutive houses. Basically, the path looks like this: (S , h1 , h2 , h3 , ... T). you have to find the shortest path from ‘S’ to ‘T’.

For example

In the below map of Ninjaland let say you want to go from S=1 to T=8, the shortest path is (1, 3, 8). You can also go from S=1 to T=8  via (1, 2, 5, 8)  or (1, 4, 6, 7, 8) but these paths are not shortest.

You will be given a stream of numbers, and you need to find the 'kth' largest number in the stream at any given time.

As the stream of numbers can not be given during compile time, so you need to design a data structure which can accept infinite numbers and can return the 'kth' largest number at any given time.

The stream of numbers is nothing but a large collection of numbers from which integers are read at runtime, such as the user will never know the upper limit on the number of integers that will be read.

The implemented data structure must support the following operations:

1. add(DATA) :
   This function should take one argument of type and store it in its pool and returns the 'kth' largest number from the current pool of integers.

You will be given 'q' queries:

val - For this query, insert the integer into your current pool of integers and return the 'kth' largest integer from the existing pool of integers.

Note

 1. The maximum number of integers that will be given will always be under memory limits.

 2. You will also be given an initial pool of integers whose size equals k.

 3. The maximum number of queries will be less than 10^5.

 4. The 'kth' largest element is not the 'kth' distinct element but the 'kth' largest element in the sorted order.

 5. There will be at least one query of type 2.

You are given a string ‘str’ of ‘N’ lowercase alphabets. Your task is to check whether it is possible to split the given string into three non-empty substrings such that one of them is a substring of another two.

For example:

‘str’ = 'abcabab', we can split this string into 3 string a, b, c as a = 'abc', b = 'ab',  c = 'abc', we can clearly see that b is a substring of both a and c.

Note:

A substring is a contiguous sequence of characters within a string. For example 'ab', 'b' and 'abc' are the substring of string 'abc', but 'ac' is not a substring of 'abc'. 

A non-empty substring means a substring with a size greater than 0.

There are ‘N’ cities numbered from 1 to ‘N’ and ‘M’ roads. Each road connectss two different cities and described as a two-way road using three integers (‘U’, ‘V’, ‘W’) which represents the cost ‘W’ to connect city ‘U’ and city ‘V’ together.

Now, you are supposed to find the minimum cost so that for every pair of cities, there exists a path of connections (possibly of length 1) that connects those two cities together. The cost is the sum of the connection costs used. If the task is impossible, return -1.

Given an integer ‘N’ representing the number of pairs of parentheses, Find all the possible combinations of balanced parentheses with the given number of pairs of parentheses.

Note :

Conditions for valid parentheses:
1. All open brackets must be closed by the closing brackets.

2. Open brackets must be closed in the correct order.

For Example :

()()()() is a valid parentheses.
)()()( is not a valid parentheses.

Explain the project I was working on in my previous company. Cross questions about the tech used, architecture, how it was used, what challenged we faced, what solutions we implemented, my role in the projects etc.

Mr. X is a busy person. He has to attend 'N' meetings throughout the day. You are given the schedule of Mr. X in a 2D Matrix 'MEETINGS' having 'N' rows and 2 columns. The 'i'th element of the first column contains the starting time of the 'i'th meeting, and the 'i'th element of the second column contains the ending time of the 'i'th meeting.

Two meetings are conflicting with each other if they overlap each other for some non-zero time. If a meeting 'X' starts at the same time as the meeting 'Y' ends, then they do not conflict.

Given the schedule of the day of Mr. X. Find the index of any one conflicting meeting for each of the 'N' meetings.

In case a particular meeting does not conflict with any meeting, take -1 as the index of the conflicting meeting for that meeting.

Note :

If there are multiple conflicting meetings for a particular meeting. You can return any one of them.

Example :

Consider the matrix MEETINGS = [ [ 1, 3 ] , [ 4, 5 ] , [ 2, 5 ] ] 

The array containing the Conflicting Meetings will be [ 3, 3, 1 ].

You are a student of Netaji Subhas Institute of Technology. You have to take ‘N’ number of courses labelled from 1 to N to complete your B.Tech Degree.

Some courses may have prerequisites, for example, to take course 1 you have to first take course 2, which is expressed as a pair: [1, 2]. Now, your task is to find is it possible for you to finish all courses.

Note: There are no duplicate pairs in the prerequisites array.

For example-

If N = 2 and prerequisite = [[1, 2]]. Then, there are a total of 2 courses you need to take. To take course 1 you need to finish course 2. So, it is possible to complete all courses.