/** File "StringClient.java".  Java version of the "Stack<T>" class in a
    textbook by Ravi Sethi, but with the argument type T fixed as String.
    By KWR for CSE250, Fall 2009, to translate into C++ as-is (Assignment 1)
    (with a derived class for extra credit).   [^^^Put your name above.]
    Later we will turn it into a C++ template class Stack<T>.
 */

// Your C++ code should be **all in one file** StringClientNNN.cc, where
// your initials go in place of NNN.  Note that C++ does *not* require the 
// filename and main-class name to match like in Java.  To repeat, in
// this exercise we are NOT doing separate .h and .cpp files yet---one
// reason is that the later template version will have to be .h-only anyway.

// Note that to be "nerdy", Java String should translate as C++ const string*.
// However, we will relax and let you use the simple C++ "string" value type.
// BUT, in other places, your code must be "const-correct"!
// Also please delete all these ugly directions/hint comments...keep just
// the /** comments and important // ones such as the CLASS INV.


import java.io.*;   // C++: use #include <iostream>
                    // Also #include <vector>

class StringStack {
   int top; 
   final int maxSize = 101;                 //C++: must init by constructor?
   String elements[] = new String[maxSize]; //C++: use vector<string>*
                                            //Nerdy: vector<const string*>* !
   //C++: ^^^^must initialize in constructor!: new vector<string>(maxSize)


   //CLASS INV: top is the /first free cell/, empty stack is top == 0;


   /** Create empty stack
    */
   public StringStack() {top = 0;}          

   public void push(String c) {
      elements[top++] = c;        //C++: elements->at(top++) = c;  is OK
   }
   public String pop() {
      if (top == 0) {
         System.err.println("Attempt to pop from empty stack."); 
         return "";               //System.err.print ~= cerr << in C++
      } else {
         return elements[--top];  //Is [--top] bad style per text, page 22?
      }                           //Well, as we'll see , it *is* STL-style!
   }                              //But you need the CLASS INV to be sure...
   public int size() { return top; }
}

//class MyStringStack extends StringStack {    //Extra Credit---
//Write a version that overrides push(...) to do the same kind of
//bounds-checking that pop() does, and add code in "main" showing it.
//Note that the regular-credit portion should use "virtual" for this reason!
//This may also induce you to add a virtual destructor (with { } body) per
//lecture advice, though the other two of the "Big 3" can be left out.
//Your MyStringStack() constructor should forward to the base-class
//constructor in the initializer list, along lines of text ch. 3, page 191.
//Looking ahead in the text is why this is extra credit.
   
public class StringClient {               //use just "int main()" in C++
   /** Test-driving code for StringStacks
    */
   public static void main(String args[]) {
      StringStack testStack = new StringStack();
      System.out.print("Pushing \"AAA\" ... ");     //use cout << ... 
      testStack.push("AAA"); 
      System.out.println("Pushing \"BBB\" ... ");   //this tacks on ...<< endl;
      testStack.push("BBB"); 
      System.out.println("Size is now " + testStack.size());
      testStack.pop();               // ^ chain with "<<" instead in C++
      System.out.println("Pop---size is now " + testStack.size());
      String c = testStack.pop();
      System.out.print("I popped the string \"");
      System.out.println(c + "\", size now " + testStack.size());
      System.out.println("Can I pop again?");
      String d = testStack.pop();
      System.out.println("Oops!  I got: \"" + d + "\"");
   }
}