Can someone help me with this lab assignment? I really do not know what should I do? This assignment
The program you wrote in Stacks 1 is incomplete. Without a destructor it creates a memory leak. A destructor has been defined in this program but it is incorrect. To visualize how the destructor works, a cout statement has been added. Fix the errors, including the cout statement, to display the value in each node of the stack before releasing the memory.
Write a loop in main() to enter an unknown number of positive integers. The loop stops when you enter 0 or a negative number. As you are entering integers, they are to be pushed onto a stack.
Ex.: If the user enters '10 20 30 -1` the output (from the destructor) should be:
30 - deleted!
20 - deleted!
10 - deleted!
Empty stack!
Ex.: If the user enters '-1` the output should be:
Empty stack!
This is the code:
#include
using namespace std;
class Stack_int
{
private:
// Structure for the stack nodes
struct StackNode {
int value; // Value in the node
StackNode *next; // Pointer to next node
};
StackNode *top; // Pointer to the stack top
int length; // Number of nodes
public:
Stack_int(){ top = NULL; length = 0; } //Constructor
~Stack_int(); // Destructor
// Stack operations
// bool isEmpty();
bool push(int);
// int pop();
// int peek();
// int getLength();
};
/**~*~*
Member function push: pushes the argument onto the stack.
*~**/
bool Stack_int::push(int item)
{
StackNode *newNode; // Pointer to a new node
// Allocate a new node and store num there.
newNode = new StackNode;
if (!newNode)
return false;
newNode->value = item;
// Update links and counter
newNode->next = top;
top = newNode;
length++;
return true;
}
/**~*~*
Destructor
*~**/
Stack_int::~Stack_int()
{
StackNode *currNode;
// Position nodePtr at the top of the stack.
currNode = top;
// Traverse the list deleting each node.
while (currNode)
{
cout << currNode->value << " - deleted!" << endl;
delete currNode;
currNode = NULL;
currNode = currNode->next;
}
cout << "Empty stack!" << endl;
}
int main() {
Stack_int s;
int item;
return 0;
}