Question

How can you implement iteration (such as checking if there are any even elements in a linked list) in a purely functional language, when there's no loop variable concept?

Answer 1

The solution of the given problem is below:

Explanation of the solution --

We can  implement iteration of of a program using the recursion concept when there is no concept of loop.

in the given problem we have to check for even number in a linked list. so we will traverse the entire linked list with given head node recursively and check if data%2==0 print them. now we will pass head->next second time in the function and check and so on till we reach the last node .

here is the screenshot of code by which u can clearly see how we can use recursion to traverse a linked list without using loop concept.

Screenshot:

  

void check(struct node *head) { if(head == NULL) { cout << "NULL" << endl; else } { if((head->data)%2==0) cout<<head->data<<< check(head->next); "; } }

here check is a function called with head node and recursively chcek every node for even number and nexr time same function called with next node i,e head->next.

Please upvote in case of anu doubts comment me.