CODE EXAMPLE FOR CPP

find node from pos linkedlist c++

// C++ program to find n'th
// node in linked list
#include <assert.h>
#include <bits/stdc++.h>
using namespace std;
 
// Link list node
class Node {
public:
    int data;
    Node* next;
};
 
/* Given a reference (pointer to
pointer) to the head of a list
and an int, push a new node on
the front of the list. */
void push(Node** head_ref, int new_data)
{
 
    // allocate node
    Node* new_node = new Node();
 
    // put in the data
    new_node->data = new_data;
 
    // link the old list
    // off the new node
    new_node->next = (*head_ref);
 
    // move the head to point
    // to the new node
    (*head_ref) = new_node;
}
 
// Takes head pointer of
// the linked list and index
// as arguments and return
// data at index
int GetNth(Node* head, int index)
{
 
    Node* current = head;
 
    // the index of the
    // node we're currently
    // looking at
    int count = 0;
    while (current != NULL) {
        if (count == index)
            return (current->data);
        count++;
        current = current->next;
    }
 
    /* if we get to this line,
    the caller was asking
    for a non-existent element
    so we assert fail */
    assert(0);
}
 
// Driver Code
int main()
{
 
    // Start with the
    // empty list
    Node* head = NULL;
 
    // Use push() to construct
    // below list
    // 1->12->1->4->1
    push(&head, 1);
    push(&head, 4);
    push(&head, 1);
    push(&head, 12);
    push(&head, 1);
 
    // Check the count
    // function
    cout << "Element at index 3 is " << GetNth(head, 3);
    return 0;
}
 
// This code is contributed by rathbhupendra