const以及入栈出栈

#include "stdafx.h"
#include <iostream>
using namespace std;

class StringStack
{
 enum{size=100};
 const char *stack[size];
 int index;
public:
 StringStack();
 void push(const char *s);
 const char *pop();
};

StringStack::StringStack():index(0)
{
    memset(stack,0,sizeof(char*)*size);
}

void StringStack::push(const char *s)
{
 if(index<size)
  stack[index++]=s;
}

const char *StringStack::pop()
{
 if (index>0)
 {
  const char*rv=stack[--index];
  stack[index]=0;
  return rv;
 }
 return 0;
}

const char* iceCream[]={
 "pralines & cream",
 "fudge ripple",
 "jamo almond fudge",
 "wild mountain blackberry",
 "raspberry sorbet",
 "lemon swirl",
 "rocky road",
 "deep chocolate fudge"
};

const int ICsz=sizeof(iceCream)/sizeof(*iceCream);

int _tmain(int argec, _TCHAR* argv[])
{
 StringStack ss;
 for (int i=0;i<ICsz;i++)
 {
  ss.push(iceCream[i]);
 }
 const char *cp;
 while ((cp=ss.pop())!=0)
 {
  cout<<cp<<endl;
 }
 getchar();
 return 0;
}