SDE - 1

Ninjas is practicing problems on the linked list. He came across a problem in which he has given a linked list of ‘N’ nodes and two integers, ‘LOW’ and ‘HIGH’. He has to return the linked list ‘HEAD’ after reversing the nodes between ‘LOW’ and ‘HIGH’, including the nodes at positions ‘LOW’ and ‘HIGH’.

You are given a Singly Linked List of integers. Return true if it has a cycle, else return false.

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

Example:

In the given linked list, there is a cycle, hence we return true.

A doubly-linked list is a data structure that consists of sequentially linked nodes, and the nodes have reference to both the previous and the next nodes in the sequence of nodes.

You are given a sorted doubly linked list of size 'n'.

Remove all the duplicate nodes present in the linked list.

Example :

Input: Linked List: 1 <-> 2 <-> 2 <-> 2 <-> 3

Output: Modified Linked List: 1 <-> 2 <-> 3

Explanation: We will delete the duplicate values ‘2’ present in the linked list.

You are given a 'M' x 'N' matrix of characters, 'CHARACTER_MATRIX' and a string 'WORD'. Your task is to find and print all occurrences of the string in the given character matrix. You are allowed to search the string in all eight possible directions, i.e. North, South, East, West, North-East, North-West, South-East, South-West.

Note: There should not be any cycle in the output path. The entire string must lie inside the matrix boundary. You should not jump across boundaries, i.e. from row 'N' - 1 to 0 or column 'N' - 1 to 0 or vice versa.

Example:

Consider below matrix of characters,
[ 'D', 'E', 'X', 'X', 'X' ]
[ 'X', 'O', 'E', 'X', 'E' ] 
[ 'D', 'D', 'C', 'O', 'D' ]
[ 'E', 'X', 'E', 'D', 'X' ]
[ 'C', 'X', 'X', 'E', 'X' ]

If the given string is "CODE", below are all its occurrences in the matrix:

'C'(2, 2) 'O'(1, 1) 'D'(0, 0) 'E'(0, 1)
'C'(2, 2) 'O'(1, 1) 'D'(2, 0) 'E'(3, 0)
'C'(2, 2) 'O'(1, 1) 'D'(2, 1) 'E'(1, 2)
'C'(2, 2) 'O'(1, 1) 'D'(2, 1) 'E'(3, 0)
'C'(2, 2) 'O'(1, 1) 'D'(2, 1) 'E'(3, 2)
'C'(2, 2) 'O'(2, 3) 'D'(2, 4) 'E'(1, 4)
'C'(2, 2) 'O'(2, 3) 'D'(3, 3) 'E'(3, 2)
'C'(2, 2) 'O'(2, 3) 'D'(3, 3) 'E'(4, 3)