Detecting a Loop in a Linked List

To detect if a linked list has a loop, we can use the Floyd's Cycle-Finding Algorithm.

The algorithm works by using two pointers, one moving at twice the speed of the other. If there is a loop in the linked list, the faster pointer will eventually catch up to the slower pointer.

Here's the C++ code for detecting a loop in a linked list using this algorithm:

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}

#include <iostream>

using namespace std;

​

// Linked List Node

class Node {

public:

    int data;

    Node* next;

​

    Node(int value) {

        data = value;

        next = nullptr;

    }

};

​

// Linked List Class

class LinkedList {

public:

    Node* head;

​

    LinkedList() {

        head = nullptr;

    }

​

    // Detecting a Loop

    bool detectLoop() {

        Node* slow = head;

        Node* fast = head;

​