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@mycodeschool
Created October 8, 2013 02:44
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An object oriented implementation of stack using arrays in C++.
// Stack - Object oriented implementation using arrays
#include <iostream>
using namespace std;
#define MAX_SIZE 101
class Stack
{
private:
int A[MAX_SIZE]; // array to store the stack
int top; // variable to mark the top index of stack.
public:
// constructor
Stack()
{
top = -1; // for empty array, set top = -1
}
// Push operation to insert an element on top of stack.
void Push(int x)
{
if(top == MAX_SIZE -1) { // overflow case.
printf("Error: stack overflow\n");
return;
}
A[++top] = x;
}
// Pop operation to remove an element from top of stack.
void Pop()
{
if(top == -1) { // If stack is empty, pop should throw error.
printf("Error: No element to pop\n");
return;
}
top--;
}
// Top operation to return element at top of stack.
int Top()
{
return A[top];
}
// This function will return 1 (true) if stack is empty, 0 (false) otherwise
int IsEmpty()
{
if(top == -1) return 1;
return 0;
}
// ONLY FOR TESTING - NOT A VALID OPERATION WITH STACK
// This function is just to test the implementation of stack.
// This will print all the elements in the stack at any stage.
void Print() {
int i;
printf("Stack: ");
for(i = 0;i<=top;i++)
printf("%d ",A[i]);
printf("\n");
}
};
int main()
{
// Code to test the implementation.
// calling Print() after each push or pop to see the state of stack.
Stack S;
S.Push(2);S.Print();
S.Push(5);S.Print();
S.Push(10);S.Print();
S.Pop();S.Print();
S.Push(12);S.Print();
}
@csgeeek
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csgeeek commented May 25, 2021

I am sorry but I have a little doubt,....we defined a function in public as Stack which sets the value of top as -1. But we never called it in the main function, then why the stack is initialized with top = -1.

Stack is a constructor.
It will be called automatically when an object is created in int main()

@itsakashp
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itsakashp commented Jun 14, 2021

But if i am not wrong, the basic functionality of pop() function in stack is to delete the recent value and also return the deleted Value to the Calling Function
.int pop(){ if (isEmpty()) { cout<<"ERROR! No Element to POP\t"; } return A[top--]; };

@Abhinav12082003
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stdio needs to be included.

actually iostream is enough in cpp language

@JoNieRv
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JoNieRv commented Jan 2, 2023

stdio needs to be included.

actually iostream is enough in cpp language

he said that because printf is used in code instead of cout.

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