Linked lists and inserting nodes (c++)

[lolcheelol]

the program runs without errors, but when i try to use the changenode function, if i put anything above 2 it doesn't change the correct node. here is the source code.

#include <iostream.h>
#include <fstream.h>
#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
#include <string.h>


typedef
struct node{
    int data1;
    node *p;
} nodetype;

nodetype *p = NULL;

void deleteAll(){
p=NULL;
}

void startlist(){
    nodetype *firstone = new nodetype;
    nodetype *temp;

    for(int i=0; i<10; i++){
        temp=new nodetype;
        temp->data1=random(1000);
    if(p == NULL){
        p=temp;
        firstone=temp;
            } // if
    else{
        firstone->p=temp;
        firstone=temp;
         } // else
                } //for
    temp->p = NULL;
} // startlist



void addNode(int pos, int value){
    nodetype *n=new nodetype;
    n->data1=value;
    nodetype *temp=p;

    if(pos==1){  n->p=p; 
            p=n;   } // if

      else{
     for(int i=0; i<pos-2; i++) temp=temp->p;
    n->p = temp->p; temp->p=n;
    } // else
    
} // addnode

void deleteNode(int pos){
    nodetype *temp=p;
    nodetype *d = new nodetype;
    if(pos==1){ 
                p=p->p;
        delete temp;
        } //if
    else{
    for(int i=0; i<pos; i++){
        d = temp;
        temp = temp->p;
       } //for
      d->p=temp->p;
        } //else

} // deletenode

void changeNode(int pos, int value){
    node *c=new nodetype;
    c->data1=value;
    nodetype *temp=p;
    for(int i=0; i<pos; i++){
        p = temp; temp=temp->p;            
        p->p=c; 
        c->p = temp;
            }

}
    
    
void printall(){
    nodetype *temp = p;

    if(temp==NULL){
        cout << "\n\n\tError";
            } // if
    else{
        while(temp!=NULL){
            cout << "  " << temp->data1;
            temp=temp->p;
      } // while
            } // else

} // printall

int listsize(){
    nodetype *temp = p;
    int size=0;
    for(;;){      
        if(temp==NULL) break;
        temp=temp->p;
        size++;
        }
    cout << "\n\n\tList size = " << size;

return size;
} 

int main(){
   clrscr();
    int pos, value;
    char c1;
    cout << "\n\n\tstartlist() ";
    startlist();
    printall();
    getch();
    cout << "\n\n\t Insert Node (Y/N)? ";
    c1=getche();
    if((c1=='Y')||(c1=='y')){
    cout << "\n\tNode# = ";
    cin >> pos;
    cout << "\n\tValue = ";
    cin >> value;
        addNode(pos,value);
        }
    cout << "\n\n\t";
    printall();
    listsize();
    cout << "\n\n\t Change Value (Y/N)? ";
    c1=getche();
    if((c1=='Y')||(c1=='y')){
    cout << "\n\tNode# = ";
    cin >> pos;
    cout << "\n\tValue = ";
    cin >> value;
        changeNode(pos,value);
        }
    cout << "\n\n\t";
    printall();
    listsize();
    cout << "\n\n\t Delete Node (Y/N/ALL)? ";
    c1=getche();
    if((c1=='Y')||(c1=='y')){
    cout << "\n\tNode# = ";
    cin >> pos;
    deleteNode(pos);
        }
    else{
    ((c1=='A')||(c1=='a'));
    cout << "\n\n\tDeleting Nodes";
    deleteAll();
        }
    printall();
    listsize();
    

   cout << "\n\n\tComplete";

       return 0;
} //MAIN

here is the program output---


startlist() 549 604 986 944 712 283 556 734 286 861

Insert Node (Y/N)? y
Node# = 9

Value = 333


549 604 986 944 712 283 556 734 333 286 861

List size = 11

Change Value (Y/N)? y
Node# = 3

Value = 333


986 333 944 712 283 556 734 333 286 861

List size = 10
~~~~~~~~~~~~~~~ ~~~~


the numbers shift to the left as u can see from the program output

[weaknessforcats]

Have you stepped through this using your debugger?

[lolcheelol]

i figured it out, i didn't need nodetype *c because it would be adding node.