Exception thrown: write access violation - c++

Question

I am trying to implement a list structure, but when I wrote the insert() function which inserts an element in a specific position in the list, I get an error Exception thrown: write access violation.
pl was 0x34812B3A.
I tried alot to fix it but I really can't. I used try..throw..catch and still didn't get it, so what should I do.
This is my code:
List.h
#pragma once
#define MAXLIST 100
typedef struct List {
int size;
int entry[MAXLIST];
}list;
void createl(list*);
int ListEmpty(list*);
int ListFull(list*);
int sizel(list*);
void destroyl(list*);
void insert(int, int, list*);
void deletei(int* , int, list*);
void traversel(list*, void (*)(int));
void retrieve(int*, int, list*);
void replace(int, int, list*);
//int access(int , list*);
and this is the implementation (List.cpp)
#include <iostream>
#include "List.h"
using namespace std;
void createl(list* pl) {
pl->size = 0;
}
int isEmpty(list* pl) {
return !(pl->size);
}
int isFull(list* pl) {
return (pl->size == MAXLIST);
}
int sizel(list* pl) {
return pl->size;
}
void destroyl(list* pl) {
pl->size = 0;
}
void insert(int e, int p, list* pl) { //insert element e in the postion p in the list
for (int i = pl->size -1; i >= p; i--) {
pl->entry[i+1] = pl->entry[i];
}
pl->entry[p] = e;
pl->size++;
}
void deletei(int* pe, int p, list* pl) {
*pe = pl->entry[p];
for (int i = p + 1; i < pl->size; ++i) {
pl->entry[i-1] = pl->entry[i];
}
pl->size--;
}
void traversel(list* pl, void (*pf)(int e)) {
for (int i = 0; i < pl->size; ++i) {
(*pf)(pl->entry[i]);
}
}
void retrieve(int* pe, int p, list* pl) {
*pe = pl->entry[p];
}
void replace(int e, int p, list* pl) {
pl->entry[p] = e;
}
/*int access(int p, list* pl) {
return pl->entry[p];
}*/
I get the error here in function insert()
pl->entry[p] = e;
and this is a program to just check if my code works.
#include <iostream>
#include "List.h"
using namespace std;
void display(int e) {
cout << e << "\n";
}
int main() {
list l;
list* ptl = &l;
int t;
cout << "Put 5 elements:\n";
for (int i = 0; i < 5; ++i) {
cin >> t;
insert(t, sizel(ptl), ptl);
}
cout << "The list looks like a stack\n\n";
traversel(ptl, display);
cout << "The size of the list is: " << sizel(ptl) << endl;
insert(9, 2, ptl);
cout << "The size of the list is: " << sizel(ptl) << endl;
int temp;
deletei(&temp, 2, ptl);
cout << temp <<endl ;
traversel(ptl, display);
cout << "The size of the list is: " << sizel(&l) << endl;
int t2;
retrieve(&t2, 2, ptl);
cout << t2 << endl;
replace(4, 1, ptl);
traversel(ptl, display);
destroyl(ptl);
cout << "The size of the list is: " << sizel(ptl) << endl;
return 0;
}
Thank you for your time and helping me.

Answer 1

You used ptl, which points at l, without initializing l.
Add initialization like this:
int main() {
list l;
list* ptl = &l;
int t;
createl(ptl); // add initialization
cout << "Put 5 elements:\n";
for (int i = 0; i < 5; ++i) {
cin >> t;
insert(t, sizel(ptl), ptl);
}