Sam is developing a new web browser and he feels that back, forward and refreshes buttons are too boring, he feels showi

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Sam is developing a new web browser and he feels that back,
forward and refreshes buttons
are too boring, he feels showing the URL of the website which they
point to would be a better
approach, he is facing trouble with this task and might be fired
from his job all because he didn’t
study an important course well in college, you being a student of
data structure and algorithms
decide to help your friend.
Following operations are possible
V <URL> : Visit the input URL
B <N> : Back N steps, in case not possible print “m back not
possible”, then print as stated
F <N> : Forwards N steps print “m forward not possible”, then
print as stated
Q <N> : Shows URL N step from the present URL (N is positive
for forward and negative for
backward, in case N is out of bound print None)
D <N> : Delete Nth step URL from the present URL (N is
positive for forward and negative for
backward, in case N is out of bound print None)
E : Exit
With each operation print (except Q and D) the URL of one step
back, present (refresh) and one
step forward.
Assumptions and Clarifications:
1 - Browser has only 1 tab
3 - Back and Forward take place one step at a time, for example, if
you want to go back 3 steps,
it would mean going back 2 steps then taking one more step
backwards and so on.
4 - If no URL is present while front or back, you need to display
“None”
Important Note: It is compulsory to use a doubly-linked list for
this assignment as your main
data structure.
Sample Input:
V google.com
V twitter.com
V google.com
B 1
F 2
Q -2
D -1
B 1
V linkedin.com
B 1
E
Output
None google.com None
google.com twitter.com None
twitter.com google.com None
google.com twitter.com google.com
1 forward Not possible
twitter.com google.com None
google.com
None google.com google.com
google.com linkedin.com None
None google.com linkedin.com
Explaination:
V google.com -
Doubly linked list:
[google.com]*
Print:
None google.com None
V twitter.com -
Doubly linked list:
[google.com] <-> [twitter.com]*
Print:
google.com twitter.com None
V google.com -
Doubly linked list:
[google.com] <-> [twitter.com] <-> [google.com]*
Print:
twitter.com google.com None
B 1
Doubly linked list:
[google.com] <-> [twitter.com]* <-> [google.com]
Print:
google.com twitter.com google.com
F 2
Doubly linked list:
After 1 forward
[google.com] <-> [twitter.com] <-> [google.com]*
Remaining 1 forward not possible
Print:
1 Forward Not possible
twitter.com google.com None
Q -2
Doubly linked list:
[google.com] <-> [twitter.com] <-> [google.com]*
Print:
google.com
D -1
Doubly linked list:
[google.com] <-> [google.com]*
B 1
Doubly linked list:
[google.com]* <-> [google.com]
Print:
None google.com google.com
V linkedin.com
Doubly linked list:
[google.com] <-> [linkedin.com]*
Print:
google.com linkedin.com None
B 1
Doubly linked list:
[google.com]* <-> [linkedin.com]
Print:
None google.com linkedin.com
E
Code terminates