Question

A Stack is a kind of data structure which can store elements with the restriction that an element can be added or removed from the top end only.

The details of the class Stack is given below:

Class name:	Stack
Data members/instance variables:
Chat[]:	array to hold the characters
size:	stores the maximum capacity of the stack
top:	to point the index of the topmost element of the stack
Member functions/methods:
Stack(int mm):	constructor to initialize the data member size = mm, top = −1 and create the character array
void push_char(char v):	to add characters from the top end if possible else display the message("Stack full")
char pop_char():	to remove and return characters from the top end, if any, else return '$'
void display( ):	to display elements of the stack

Specify the class Stack giving the details of void push_char(char) and char pop_char( ). Assume that the other functions have been defined.

The main( ) function and algorithm need NOT be written.

Answer 1

class Stack
{
    char cha[];
    int top;
    int size;
    void push_char(char v)
    {
      if (top==size-1)
        System.out.println("Stack full !!!!");
      else
        cha[++top]=v;
    }
    char pop()
    {
      If (top==-1)
      return ("$");
      else
      {
        char c= cha[top];
        top=top-1;
        return c;
      }
    }
}