Removing cycle from linked list

#1

I am unable to remove the cycle from the link list. I am unable to understand what is the bug in the program pls help me to solve it.

#2

hello @guptamuskan1305
pls save ur code here -> https://ide.codingblocks.com/
and share the link with me

#3
#4

you are not reading input correctly.

this how u should take input for list which can have cycle
Say If INPUT IS 1 2 3 4 5 2 3 -1
form a linked list 1->2->3->4>5 then you see that 2 has already been visited (So for this you can maintain a map or a visited array…whenever you see that a node is already visited, connect next pointer of previous node to that node.) so connect the next pointer of 5 to 2. This way you have created the circular linked list .

void buildCycleList(Node *&head)
{
    unordered_map<int, Node *> hash;
    int x;
    cin >> x;
    if (x == -1)
    {
        head = NULL;
        return;
    }
    head = new Node(x);
    hash[x] = head;
    Node *current = head;
    while (x != -1)
    {
        cin >> x;
        if (x == -1)
            break;
        if (hash.find(x) != hash.end())
        {
            current->next = hash[x];
            continue;
        }
        Node *n = new Node(x);
        current->next = n;
        current = n;
        hash[x] = n;
    }
    current->next = NULL;
}
#5

I don’t need to create a cycle I need to delete one

#6

yeah you have to delete cycle ,but for that first u need to build cyclic linked list from the given input, and for that u should follow what i said above