Fullstack Developer

This was an easy problem and the interviewer just asked my approach, and he was happy.
1) There are four directions in which we have to traverse - 
Left to Right → Top to Bottom → Right to Left → Bottom to Top
(By this observation, we decided to use four for loops for each of the direction)

2) With each traversal on either of the four directions, one row/column is traversed.
(By this observation, we came to a conclusion that we need to track the count of row/column visited
for all the four directions)

3) And we need to keep doing the above steps until a boundary condition is met. So, for that we can count 
the number of elements in the matrix and when element count becomes (m x n), we can break from the loop.

We have to traverse the linkedlist and have to ignore the duplicates by changing the link
by accessing the prev and ptr->next pointer which are neighbours of duplicate elements ,those pointers will help to remove the duplicate.