C++ Program to find Nth node in Linked List

C++ Program to find Nth node in Linked List

In this example, we'll see a C++ program through which we will find a node in a Linked list.

• Step 1: First, declare the recursive function with parameters (Node * head, int data).
• Step 2: Then, Put the Node *temp = head, int index = 0;
• Step 3: Repeat Step 4 and Step 5 while (temp!= NULL)
• Step 4: if(temp -> data == data) then return index.
• Step 5: else index++ and temp = temp->next; then return -1.

#include <bits/stdc++.h>
using namespace std;
struct Node{// linked list Node
int data;
Node * next;
};
Node *newNode(int k){ //defining new node
Node *temp = (Node*)malloc(sizeof(Node)); 
temp->data = k; 
temp->next = NULL; 
return temp; 
}
//Used to add new node at the end of the list
Node *addNode(Node* head, int k){
if(head == NULL){
head = newNode(k);
}
else{
Node * temp = head;
Node * node = newNode(k);
while(temp->next!= NULL){
temp = temp->next;
}
temp-> next = node;
}
return head;
}
// Used to create new linked list and return head
Node *createNewLL(){
int cont = 1;
int data;
Node* head = NULL;
while(cont){
cout<<"Enter the data of the Node"<<endl;
cin>>data;
head = addNode(head,data);
cout<<"Do you want to continue?(0/1)"<<endl;
cin>>cont;
}
return head;
}
//Function for finding the node
int findNodeInLL(Node* head, int data){
//Used to keep track of the Node Index
int index = 0;              
Node * temp = head;
//LinkedList traversal for finding the node
while(temp!=NULL){
if(temp->data == data){         
//If element found return index
return index;               
}
temp = temp->next;
index++;
}   
//If element not found
return -1;                  
}
//Driver Main
int main(){
Node * head = createNewLL();
int data;
cout<<"Enter the data of the linked list to be found."<<endl;
cin>>data;
int index = findNodeInLL(head,data);
cout<<"It is present at "<<index<< endl;
return 0;
}