System Engineer Specialist

Ninja has been given a number that is represented in the form of a linked list such that each digit corresponds to a node. He has been asked to add 1 to it and return the updated list.

For Example:

1234 is represented as (1 -> 2 -> 3 -> 4) and adding 1 to it should change it to (1 -> 2 -> 3 -> 5).

Note:

The input Linked list does not have any trailing zeros.

You are given two strings S and X containing random characters. Your task is to find the smallest substring in S which contains all the characters present in X.

Example:

Let S = “abdd” and X = “bd”.

The windows in S which contain all the characters in X are: 'abdd', 'abd', 'bdd', 'bd'. 
Out of these, the smallest substring in S which contains all the characters present in X is 'bd'. 
All the other substring have a length larger than 'bd'.

There is a directed graph consisting of ‘N’ nodes numbered from 0 to ‘N’-1. You are given a list ‘EDGES’ of size ‘M’, consisting of all the edges of this directed graph, and two nodes ‘SRC’ and ‘DEST’ of this graph. Determine whether or not all paths starting from node ‘SRC’ eventually end at node ‘DEST’, that is -:

1. At least one path exists from node ‘SRC’ to node ‘DEST’.

2. If there exists a path from the node ‘SRC’ to a node with no outgoing edges, then that node must be ‘DEST’.

3. There should be a finite number of paths from ‘SRC’ to ‘DEST’.

You should return True if all paths starting from node ‘SRC’ eventually end at node ‘DEST’, Otherwise, return False. See the example for more clarity.

Note :

1. The given graph may have self-loops and parallel edges.

Example :

Consider ‘N’ = 4, ‘EDGES’ = [[0, 1], [0, 3], [1, 2], [3, 2]],  ‘SRC’ = 0 and ‘DEST’ = 2. The given directed graph is shown below.

Here, all the paths that start from node 0 are -:
1. 0->1->2
2. 0->3->2
Both of these paths eventually end at node ‘2’ i.e node ‘DEST’. Thus we should return True.

You are given a Singly Linked List of integers. You have to return true if the linked list is palindrome, else return false.

A Linked List is a palindrome if it reads the same from left to right and from right to left.

Example:

The lists (1 -> 2 -> 1), (3 -> 4 -> 4-> 3), and (1) are palindromes, while the lists (1 -> 2 -> 3) and (3 -> 4) are not.

Given a binary tree of integers, you are supposed to modify the given binary tree to a sum tree where each node value is replaced by the sum of the values of both left and right subtrees in the given tree. The value of leaf nodes is changed to zero.

Example:

Below is the example showing the input tree and its sum tree.  

You have been given two Strings “STR1” and “STR2” of characters. Your task is to find the length of the longest common subsequence.

A String ‘a’ is a subsequence of a String ‘b’ if ‘a’ can be obtained from ‘b’ by deletion of several (possibly, zero or all) characters. A common subsequence of two Strings is a subsequence that is common to both Strings.