Find the Length of Loop in Linked List

We modify the Floyd's Loop/Cycle Detection Algorithm that we saw in the previous Post to find the count of Nodes which are part of the Linked List.

int count_loop_lenth(Node *node){

    int count = 1;

    Node *curr = node;

    while(curr->next != node){

        curr = curr->next;

        ++count;

    }

    return count;

}

int detect_loop_floyd(Node *head){

    Node *slow = head;

    Node *fast = head;

    while(slow && fast && fast->next){

        slow = slow->next;

        fast = fast->next->next;

        if(slow == fast){

            return count_loop_lenth(slow);

        }

    }

    return 0;

}

Watch detailed Explanation on Youtube.

Subscribe to KnowledgeCenter