/* stack.h: header file */
void push( char );
char pop();
int empty();
int full();
-----------------------------

/* stack.c: stack implem */
#include "stack.h"


#define MAXSTACK 10
#define EMPTYSTACK -1
int top = EMPTYSTACK;
char items[MAXSTACK];




void push(char c) {
   items[++top] = c;
}

char pop() {
   return items[top--];
}

int full()  {
   return top+1 == MAXSTACK;
}

int empty()  {
   return top == EMPTYSTACK;
}

-----------------------------
/* stackmain.c: use stack */
#include <stdio.h>
#include "stack.h"

int main() {


   char ch;
   while ((ch = getchar())
         != '\n')
      if (!full()) push(ch);
   while (!empty())
      printf("%c", pop());
   printf("\n");
   return 0;
}

// stack.h: header file
class Stack {
   int MaxStack;
   int EmptyStack;
   int top;
   char* items;
public:
   Stack(int);
   ~Stack();
   void push(char);
   char pop();
   int empty();
   int full();
};
-------------------------------
// stack.cpp: stack functions
#include "stack.h"

Stack::Stack(int size) {
   MaxStack = size;
   EmptyStack = -1;
   top = EmptyStack;
   items = new char[MaxStack];
}

Stack::~Stack() {delete[] items;}

void Stack::push(char c) {
   items[++top] = c;
}

char Stack::pop() {
   return items[top--];
}

int Stack::full()  {
   return top + 1 == MaxStack;
}

int Stack::empty()  {
   return top == EmptyStack;
}

-------------------------------
// stackmain.cpp: use stack
#include <iostream.h>
#include "stack.h"

int main() {

   Stack s(10); // 10 chars
   char ch;
   while ((ch = cin.get()) 
         != '\n')
      if (!s.full()) s.push(ch);
   while (!s.empty())
      cout << s.pop();
   cout << endl;
   return 0;
}

// Stack.java: stack implementation
public class Stack {
   private int maxStack;
   private int emptyStack;
   private int top;
   private char[] items;




   



   



   public Stack(int size) {
      maxStack= size;
      emptyStack = -1;
      top = emptyStack;
      items = new char[maxStack];
   }

   

   public void push(char c) {
      items[++top] = c;
   }

   public char pop() {
      return items[top--];
   }

   public boolean full()  {
      return top + 1 == maxStack;
   }

   public boolean empty()  {
      return top == emptyStack;
   }
}
---------------------------------------
// Stackmain.java: use the stack
import java.io.*;
public class Stackmain {

  public static void main(String[] args)
       throws IOException {
    Stack s = new Stack(10); // 10 chars
    char ch;
    while ((ch = (char)System.in.read())
          != '\n')
       if (!s.full()) s.push(ch);
    while (!s.empty())
       System.out.print(s.pop());
    System.out.println();
  }
}

% cc -o stack stack.c stackmain.c
% stack
mississippi
ppississim

% CC -o stack stack.cpp stackmain.cpp
stack.cpp:
stackmain.cpp:
% stack
mississippi
ppississim

% javac Stack.java
% javac Stackmain.java
% java Stackmain
mississippi
ppississim