Added the code for Detection of Floyd's Cycle in c++ with comments for understanding.

Adding-Floyd-cycle-detection-algorithm.cpp

@@ -0,0 +1,79 @@
+/*Floyd’s cycle finding algorithm or Hare-Tortoise algorithm is a pointer algorithm that uses only two pointers, moving through the sequence at different speeds. This algorithm is used to find a loop in a linked list. It uses two pointers one moving twice as fast as the other one. The faster one is called the fast pointer and the other one is called the slow pointer.*/
+
+                //***** Code for Detection of Floyd's Cycle in C++ *****
+
+#include <bits/stdc++.h>
+using namespace std;
+
+class Node {
+public:
+	int data;
+	Node* next;
+
+	Node(int data)
+	{
+		this->data = data;
+		next = NULL;
+	}
+};
+
+// initialize a new head for the linked list
+Node* head = NULL;
+class Linkedlist {
+public:
+	// insert new value at the start
+	void insert(int value)
+	{
+		Node* newNode = new Node(value);
+		if (head == NULL)
+			head = newNode;
+		else {
+			newNode->next = head;
+			head = newNode;
+		}
+	}
+
+	// detect if there is a loop in the linked list
+	bool detectLoop()
+	{
+		Node *slowPointer = head,
+			*fastPointer = head;
+
+		while (slowPointer != NULL
+			&& fastPointer != NULL
+			&& fastPointer->next != NULL) {
+			slowPointer = slowPointer->next;
+			fastPointer = fastPointer->next->next;
+			if (slowPointer == fastPointer)
+				return 1;
+		}
+
+		return 0;
+	}
+};
+
+int main()
+{
+	Linkedlist l1;
+	// inserting new values
+	l1.insert(10);
+	l1.insert(20);
+	l1.insert(30);
+	l1.insert(40);
+	l1.insert(50);
+
+	// adding a loop for the sake of this example
+	Node* temp = head;
+	while (temp->next != NULL)
+		temp = temp->next;
+
+	temp->next = head;
+
+	// loop added;
+
+	if (l1.detectLoop())
+		cout << "Loop exists in the Linked List\n"<<endl;			
+	else
+		cout << "Loop does not exists in the Linked List\n"<<endl;
+	return 0;
+}