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An Example Stack¶

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

Program that demonstrates an example stack data structure in C++¶

ch1_stac1.cpp

// Test of ch_stack by reversing a string.
#include "ch_stac1.h"
#include <iostream>

using namespace std;

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

    cout << str << endl;
    reset(&s);
    while (str[i] && !full(&s))
        push (&s, str[i++]);
    while (!empty(&s))
        cout << pop(&s);
    cout << endl;
}

ch_stac1.h

// A simple implementation of type ch_stack

const int max_len = 1000;
enum { EMPTY = -1, FULL = max_len -1 };

struct ch_stack
{
    char s[max_len];
    int top;
};

// A standard set of ch_stack operations.

void reset(ch_stack * stk)
{
    stk -> top = EMPTY;
}

void push(ch_stack * stk, char c)
{
    stk -> s[++stk -> top] = c;  
}

char pop(ch_stack * stk)
{
    return (stk -> s[stk -> top--]);
}

char top(ch_stack * stk)
{
    return (stk -> s[stk -> top]);
}

bool empty(const ch_stack * stk)
{
    return (stk -> top == EMPTY); 
}

bool full(const ch_stack * stk)
{
    return (stk -> top == FULL);
}

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_4_3_An_Example_Stack"

os.chdir(code_dir)

build_command = os.system("g++ ch_stac1.cpp -w -o ch_stac1")

exec_status = os.system("./ch_stac1")

My name is Betty Dolsberry!
!yrrebsloD ytteB si eman yM