Staque program pops up visual studio error [closed] - c++

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Whenever I try to launch the program it tells me this:
"Microsoft Visual Studio
There were build errors. Would you like to continue and run the last successful build?"
The assignment that this code is based on:
Create a data structure called “Staque” which can store only integers. The way Staque works is as follows:
If the number that you are trying to store in the Staque is even, it is pushed in front of the Staque
If the number that you are trying to store in the Staque is odd, it is pushed at the end of the Staque
When you try to remove a number from the Staque, you always do it from either the front or from the back of the Staque following the LIFO rule.
Write a C++ code to implement a Staque. Since the data structure is all about inserting and deleting numbers, it would be a good option to use a linked list to implement Staque. Here’s how your user interface should like:
Insert the numbers 1, 3, 2, 4, 6, 8 9 in the Staque.
Display the Staque: This is how the Staque will look like given that the above numbers were pushed in the Staque in the order given above: (front) 8 6 4 2 1 3 9 (back)
Delete 2 even numbers and 1 odd number from the Staque and then display the Staque:
Since deletion always follows the LIFO order, the numbers to be removed are 8 first and then 6(the 2 even numbers) and 9(odd) from the back of the Staque. The Staque shall then look like: (front) 4 2 1 3 (back).
Run you program for at least 3 different input series & corresponding 3 different removal series.
Here is my code:
'
#include<iostream>
#include<cstdlib>
using namespace std;
struct node {
int info;
struct node* next;
};
class Staque {
private:
struct node* head;
int size;
public:
struct node* createNewNode(int);
void insertAtFront(int);
void insertAtLast(int);
void deleteFromFront();
void deleteFromLast();
void displayList();
Staque() {
head = NULL;
size = 0;
}
};
struct node* Staque::createNewNode(int value) {
struct node* temp;
temp = new(struct node);
temp->info = value;
temp->next = NULL;
return temp;
}
void Staque::insertAtFront(int value) {
struct node* temp, * p;
temp = createNewNode(value);
if (head == NULL) {
head = temp;
head->next = NULL;
}
else {
p = head;
head = temp;
head->next = p;
}
cout << "\nElement inserted at front successfully.";
size++;
}
void Staque::insertAtLast(int value) {
struct node* temp, * s;
temp = createNewNode(value);
if (head == NULL) {
head = temp;
head->next = NULL;
}
else {
s = head;
while (s->next != NULL) {
s = s->next;
}
temp->next = NULL;
s->next = temp;
}
cout << "\nElement inserted at end successfully.";
size++;
}
void Staque::deleteFromFront() {
if (size == 0)
return;
struct node* s;
s = head;
if (head == NULL) {
cout << "\nThe staque is Empty";
return;
}
if (s->info % 2 == 0) {
head = head->next;
free(s);
size--;
cout << "\nEven element deleted.";
if (size == 0)
head = NULL;
}
}
void Staque::deleteFromLast() {
if (size == 0)
return;
struct node* s, * temp;
s = head;
if (head == NULL) {
cout << "\nThe staque is Empty";
return;
}
while (s->next != NULL) {
temp = s;
s = s->next;
}
if (s->info % 2 != 0) {
temp->next = NULL;
free(s);
size--;
cout << "\nOdd element deleted";
if (size == 0)
head = NULL;
}
}
void Staque::displayList() {
struct node* temp;
if (head == NULL) {
cout << "\nThe staque is Empty";
return;
}
temp = head;
cout << "\nElements of staque are: ";
while (temp != NULL) {
cout << temp->info << " ";
temp = temp->next;
}
cout << endl;
}
//main function
int main() {
int choice, value;
Staque sq;
while (1) {
cout << endl << "\nMenu:";
cout << "\n1.Insert ";
cout << "\n2.Delete even number";
cout << "\n3.Delete odd number";
cout << "\n4.Display staque";
cout << "\n5.Exit " << endl;
cout << "\nEnter choice : ";
cin >> choice;
switch (choice) {
case 1:
cout << "\nEnter integer to insert: ";
cin >> value;
if (value % 2 != 0) {
sq.insertAtLast(value);
}
else {
sq.insertAtFront(value);
}
break;
case 2:
sq.deleteFromFront();
break;
case 3:
sq.deleteFromLast();
break;
case 4:
sq.displayList();
break;
case 5:
exit(0);
}
}
return 0;
}
'
error message from the output:
error C4703: potentially uninitialized local pointer variable 'temp' used
1>Done building project "Staque.vcxproj" -- FAILED.
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

Answer 1

Replace
while (s->next != NULL) {
temp = s;
s = s->next;
}
with
do {
temp = s;
s = s->next;
} while (s != nullptr);
Otherwise Staque::deleteFromLast() can't delete an odd element if it is a single element in the list. Moreover temp is left uninitialized.