To reverse a number following steps should be performed:
Take the number’s modulo by 10
Multiply the reverse number by 10 and add modulo value into the reverse number.
Divide the number by 10.
Repeat above steps until number becomes zero.

Pseudocode :
reverse(n){

rev = 0; // reversed number
rem; // initialise a variable to store remainder

while(n>0){

This can be solved both: recursively and iteratively.
The recursive approach is more intuitive. First reverse all the nodes after head. Then we need to set head to be the final node in the reversed list. We simply set its next node in the original list (head -> next) to point to it and sets its next to NULL. The recursive approach has a O(N) time complexity and auxiliary space complexity....