If suppose i want to implement a stack in c using arrrays is it better to do it via making a structure or class for storing the location of head and stuff like that or should you implement in more of a hard code style like this -

#include <iostream>
using namespace std;
int stack[100], n=100, top=-1;
void push(int val) {
   if(top>=n-1)
   cout<<"Stack Overflow"<<endl;
   else {
      top  ;
      stack[top]=val;
   }
}
void pop() {
   if(top<=-1)
   cout<<"Stack Underflow"<<endl;
   else {
      cout<<"The popped element is "<< stack[top] <<endl;
      top--;
   }
}
void display() {
   if(top>=0) {
      cout<<"Stack elements are:";
      for(int i=top; i>=0; i--)
      cout<<stack[i]<<" ";
      cout<<endl;
   } else
   cout<<"Stack is empty";
}
int main() {
   int ch, val;
   cout<<"1) Push in stack"<<endl;
   cout<<"2) Pop from stack"<<endl;
   cout<<"3) Display stack"<<endl;
   cout<<"4) Exit"<<endl;
   do {
      cout<<"Enter choice: "<<endl;
      cin>>ch;
      switch(ch) {
         case 1: {
            cout<<"Enter value to be pushed:"<<endl;
            cin>>val;
            push(val);
            break;
         }
         case 2: {
            pop();
            break;
         }
         case 3: {
            display();
            break;
         }
         case 4: {
            cout<<"Exit"<<endl;
            break;
         }
         default: {
            cout<<"Invalid Choice"<<endl;
         }
      }
   }while(ch!=4);
   return 0;
}

Im just trying to know what is a more accepted method.

CodePudding user response：

The approach you've taken here using global variables is fine for a simple implementation, but it has a major drawback in most real-world applications: it's not reusable.

What if you need two stacks in your program? That would require creating a second set of global variables and a second set of functions to act on them.

That is the problem that using a class solves. If you wrap all of your stack's state in a class then you can create a single set of functions that can operate on any object of that class. Then creating a second stack is very simple.

Of course, for most real world applications you shouldn't implement your own stack anyway. Just use std::stack unless you have a very compelling reason not to. But that still supports the same conclusion. Because std::stack is a self-contained, reusable class any program can use it without having to re-implement their own stack logic (possibly multiple times).