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Access: Private and Public¶

Adapted from: “Object-Oriented Programming Using C++” by Ira Pohl (Addison- Wesley)

Program that demonstrates private and public access of object items in C++¶

ch_stac3.cpp

// Reverse a string with a ch_stack.
#include <iostream>
#include "ch_stac3.h"

using namespace std;

int main ()
{
    ch_stack s;
    char str[40] = {"My name is Don Knuth!"};
    int i = 0;

    cout << str << endl;
    s.reset();  // s.top = EMPTY would be illegal

    while (str[i] && !s.full())
    {
        s.push(str[i++]);
    }

    while (!s.empty())      // print the reverse
    {
        cout << s.pop();
    }

    cout << endl;
}

ch_stac3.h

struct ch_stack {
    public:
        void reset ()       { top = EMPTY; }
        void push (char c)  { top++; s[top] = c; }
        char pop ()         { return s[top--]; }
        char top_of ()      { return s[top]; }
        bool empty ()       { return ( top == EMPTY ); }
        bool full ()        { return ( top == FULL  ); }

    private:
        enum 
        {  
            max_len = 100,
            EMPTY = -1,
            FULL = max_len-1
                
        };

        char s[max_len];
        int top;
};

The above program is compiled and run using Gnu Compiler Collection (g++):

import os
root_dir = os.getcwd()

code_dir = root_dir + "/" + "Cpp_Code/Chapter_5_2_Access_Private_and_Public"

os.chdir(code_dir)

build_command = os.system("g++ ch_stac3.cpp -w -o ch_stac3")

exec_status = os.system("./ch_stac3")

My name is Don Knuth!
!htunK noD si eman yM