My code showing segmentation fault

#1
#2

Your code is giving runtime error because your circular linked list is not being formed.
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 connect the next pointer of 5 to 2. This way you have created the circular linked list . After that just detect the cycle, remove the cycle, print the new linked list.
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.

#3

1 2 3 4 5 6 2 3 -1 1–>2–>3–>4–>5–>2–>3–> Segmentation fault (core dumped)

#4

sir this is the output that is being shown by my compiler

#5

ddd
ddd1290×466 13.3 KB

Your buildlist function is not forming a circular linked list.
If it would have formed a circular linked list, then without removing the loop(from where circular linked list begins, here it is 2), this while loop in the print function would never end. I have commented out your runner function to check the actual linked list formed after taking the inputs.

#6

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. This way you can form a circular linked list

#7

sir i am unable to create circular linked list how can i make it?

#8

SharedScreenshot
SharedScreenshot952×838 91.3 KB

#9

sir ye code likha to he but wrong he

#10 

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];
            return;
        }
        Node *n = new Node(x);
        current->next = n;
        current = n;
        hash[x] = n;
    }
    current->next = NULL;
}

You can do something like this. Dry run and check

#11

for this i have to first learn what is hash

#12

int he above example of 1 2 3 4 5 2 3
we first have to connect 5 with 2 but then it will run into an infinite loop. so to cure it we have to point 3 to null right?

#13

You have to make a circular loop,
Once you connect the next of 5 to 2, circular loop is formed. The input after that ie. 3 does not even matter .

#14

pr sir jb me output print karunga…cout<<head;
to meri loop ending condition kya hogi in print function.
pehle hm likhte the while(temp!=null)…ab kya likhenge

#15

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