What is wrong with the delete section? [closed] - c++

Question

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center.
Closed 10 years ago.
Here is my code. The problem that I am getting is that I can't make work the deleter part. I want to delete one element of the structure. Here is a basic structure that you add, search and delete elements that are added. Also the elements are sorted in increasing order.
#include <iostream>
using namespace std;
struct el {
int key;
el *next;
} *start;
void init();
void add(int n);
void list();
void search(int n); // ima za dopylvane
void deleter(int n);
void main() {
init();
int n, num;
do {
cout << "\n Menu\n";
cout << "\n1 - Add element";
cout << "\n2 - List elements";
cout << "\n3 - Searching for element";
cout << "\n4 - Delete element";
cout << "\n5 - Exit";
cout << "\n Your choice:";
cin >> n;
switch (n) {
case 1:
{
cout << "\n Input num:";
cin >> num;
add(num);
break;
}
case 2:
{
list();
break;
}
case 3:
{
cout << "\n Input num for searching:";
cin >> num;
search(num);
break;
}
case 4:
{
cout << "\n Input num for deleting:";
cin >> num;
deleter(num);
break;
}
}
}
while (n != 5);
}
void list() {
el *p = start;
if (start) while (p) {
cout << p->key << " ";
p = p->next;
} else cout << "\n Empty list";
}
void init() {
start = NULL;
}
void add(int n) {
el *p = start;
if (!start) {
start = new el;
start->key = n;
start->next = NULL;
} else {
if (start->key > n) {
start = new el;
start->key = n;
start->next = p;
} else {
el * q;
while ((p->key < n) && (p->next)) {
q = p;
p = p->next;
}
if (p->key > n) {
el *s;
s = new el;
s->key = n;
s->next = p;
q->next = s;
} else {
el *s;
s = new el;
s->key = n;
s->next = NULL;
p->next = s;
}
}
}
}
void search(int n) {
el *p = start;
if (!start) cout << "\nEmpty list!";
else while ((p->key != n) && (p-> next))
p = p->next;
if (p->key == n) cout << "\nYes!";
else cout << "\nNo!";
}
void deleter(int n) {
el *p = start;
if (!start) cout << "Enfsad";
else while ((p->key != n) && (p->next)) {
n = start->key;
start = start->next;
delete p;
}
}

Answer 1

Your deleter function should be like this.
void deleter (int n)
{
el *p = start;
el *prev = p;
if (!start)
{
cout<<"Enfsad";
}
if(start->key == n)
{
start = start->next;
delete prev;
}
else
{
while (p)
{
if(p->key == n)
{
prev->next = p->next;
p->next = NULL;
delete p;
break;
}
prev = p;
p = p->next;
}
}
}
Although I think you need to check how a good linked list should be.