C++ I have a small question in this piece of code. I wanna add that if a positio

Question

C++ I have a small question in this piece of code. I wanna add that if a position is not found return -1; & if we reach the end of the list or node not found. Please if you do not know don't answer it. and no it is not as simple as:

ListNode *n = head;
    if (n == NULL) return -1; //This would be wrong!!!!!!!!!!! and totally wrong so please chegg answerers don't answer if you do not know

int NumberList::removeByPosition(int position)

{

    ListNode *n = head;
    if (n == NULL) return;
  
    while (position > 0 && n)
    {
    n = n->next;
    position--;
    }
    if (n == head)
    {
    head = head->next;
    delete n;
    return;
    }
    else
    {
    if (n == NULL) return;
    ListNode *rear = head;
    while (rear->next != n)
    rear = rear->next;
    rear->next = n->next;
    delete n;
    }
}

Explanation / Answer

I will Provide whole running code

#include <bits/stdc++.h>
using namespace std;

struct ListNode
{
int data;
struct ListNode *next;
};

void push(struct ListNode** head, int new_data)
{
struct ListNode* new_node = (struct ListNode*) malloc(sizeof(struct ListNode));
new_node->data = new_data;
new_node->next = (*head);
(*head) = new_node;
}

void removeByPosition(struct ListNode **head, int position)
{
int k=1;
if (*head == NULL)
return;

struct ListNode* p, *q;
p= *head;
if(position==1){
*head=(*head)->next;
free(p);
return ;

}
else{
while( p!=NULL && k<position)
{
k++;
q=p;
p=p->next;

}
if(p==NULL)
{
printf("Postion does not exist");
return ;
}
else{
q->next=p->next;
free(p);
}

}
}

void printList(struct ListNode *node)
{
while (node != NULL)
{
printf(" %d ", node->data);
node = node->next;
}
}

int main()
{
struct ListNode* head = NULL;

push(&head, 7);
push(&head, 1);
push(&head, 3);
push(&head, 2);
push(&head, 8);

puts("Created Linked List: ");
printList(head);
removeByPosition(&head, 4);
puts(" Linked List after Deletion at position 4: ");
printList(head);
return 0;
}

int NumberList::removeByPosition(ListNode **head,int position)
{
int k=1;
ListNode *p,*q;
if(*head==NULL)
return -1;
p=*head;
if(position==1){
*head=(*head)->next;
free(p);
return ;

}
else{
while( p!=NULL && k<position)
{
k++;
q=p;
p=p->next;

}
if(p==NULL)
{
cout<<"Postion does not exist";
return -1;
}
else{
q->next=p->next;
free(p);
}

}
}

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