Simple link list implementation using struct and functions

simple_linked_list.cpp

#include <iostream>

using namespace std;

struct ListNode
{
    int data;
    ListNode *next;

};

ListNode* GetNewNode(int userData = 0,bool userInput = false)
{

    ListNode *Node = new ListNode;
    if(userInput == true)
    {
        cin>>Node->data;
    }
    else
    {
        Node->data = userData;
    }

    Node->next = NULL;
    return Node;
}

void DeleteNode(ListNode*& Head,int position)
{
    ListNode* tmp = Head;

    if(position > 0)
    {
        for(int i=0; i<(position-1) && tmp != NULL; i++)
        {
            tmp = tmp->next;
        }


        ListNode* toDelete = tmp->next;

        tmp->next = toDelete->next;

        delete toDelete;
    }
    else
    {
        Head = tmp->next;
        delete tmp;

    }
}

void printList(ListNode *Head)
{
    ListNode *tmp = Head;

    cout<<endl;
    while(tmp != NULL)
    {
        cout<<tmp->data<<" ";
        tmp = tmp->next;
    }
    cout<<endl;
}



int SearchNode(ListNode* Head,int needle)
{
    ListNode *tmp = Head;

    for(int i = 0; tmp != NULL ; i++)
    {
        if(tmp->data == needle)
        {
            return i;
        }
        tmp = tmp->next;
    }
    return -1;
}

void insertBeg(ListNode*& Head,int value)
{
    ListNode* newNode = GetNewNode(value);

    newNode->next = Head;

    Head = newNode;
}

void insertAfter(ListNode* Head,int afterVal, int value)
{
    ListNode * tmp = Head;

    bool found = false;

    while(tmp != NULL)
    {
        if(tmp->data == afterVal)
        {
            ListNode* newNode = GetNewNode(value);
            newNode->next = tmp->next;
            tmp->next = newNode;
            found = true;
        }
        tmp = tmp->next;

        if(found== false && tmp->next == NULL)
        {
            break;
        }
    }

    if(found == false)
    {
        ListNode* newNode = GetNewNode(value);
        tmp->next = newNode;
    }

}



int main()
{
    cout<<"How many link list items do you want?"<<endl;
    int sz = 0;
    cin>>sz;

    ListNode *Head;
    ListNode *Node = GetNewNode(0,true);
    Head = Node;

    for(int i = 1; i<sz; i++)
    {
        Node->next = GetNewNode(i,true);
        Node = Node->next;
    }


    printList(Head);



    cout<<"Want to delete a item? enter position:"<<endl;
    int pos;
    cin>>pos;

    DeleteNode(Head,pos);

    printList(Head);


    {
        int needle;
        cout<<"Search item: ";
        cin>>needle;

        int x = SearchNode(Head,needle);

        if(x>=0)
        {
            cout<<"FOUND at "<<x<<endl;
        }
        else cout<<"NOT FOUND"<<endl;
    }
    printList(Head);

    {
        int needle,val;
        cout<<"Insert after item: ";
        cin>>needle;
        cout<<"Insert item value: ";
        cin>>val;

        insertAfter(Head,needle,val);
    }

    printList(Head);

    {
        int val;
        cout<<"Insert at start? ";
        cin>>val;
        cout<<endl;

        insertBeg(Head,val);
    }

    printList(Head);


    return 0;
}