Inherit constructor Memory Back Trace

[grh1107]

currently I'm rewriting old euler solutions into classes so i can store them in a library. I wrote a program that digitizes a number so it can check to see if it a pallindrome, The base class digitize dynamically allocates memory for the size of a number and stores each digit, My second class pallindrome inherits the members of digitize, and refrences the constructor using the :, however when I construct the pallindrome class i get a back trace error. I know I can probably just not use inheritance and it will work but i want to know why this is occur, but i want to inherit it, how can i fix this?

the error message looks like this

*** glibc detected *** /home/developer/workspace/Eruler/4- Palindrome/Debug/4- Palindrome: double free or corruption (fasttop): 0x000000000241b010 ***
======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6(+0x78a8f)[0x7f0e84df9a8f]
/lib/x86_64-linux-gnu/libc.so.6(cfree+0x73)[0x7f0e84dfd8e3]
/home/developer/workspace/Eruler/4- Palindrome/Debug/4- Palindrome[0x400b25]
/home/developer/workspace/Eruler/4- Palindrome/Debug/4- Palindrome[0x400b81]
/home/developer/workspace/Eruler/4- Palindrome/Debug/4- Palindrome[0x400aa0]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xff)[0x7f0e84d9feff]
/home/developer/workspace/Eruler/4- Palindrome/Debug/4- Palindrome[0x4007e9]
======= Memory map: ========

#include <iostream>
#include <math.h>
using namespace std;

typedef unsigned long long _uint64;
class Digitize
{
 protected:
    int * number;
    int Digits;
 public:
    Digitize(_uint64);
    ~Digitize() {delete [] number;}
    void Display();
};

Digitize::Digitize(_uint64 x)
{
    int y = 0, tmp = x;
    while(tmp!=0) tmp/=10, y++;
    Digits = y, number = new int[y];
    for(int c=y-1; c>=0; c--, x/=10)
        number[c]=x%10;
}

void Digitize::Display()
{
    int D=0;
    while (D<Digits)
    {
        cout << number[D] << " ";
        D++;
    }
        cout << endl;
}

class Pallindrome : public Digitize
{
  public:
    Pallindrome(_uint64 Con) : Digitize(Con) {};
    ~Pallindrome (){delete [] number;}
    bool ispallindrome ();
};

bool Pallindrome::ispallindrome()
{
    for (int start = 0, end=Digits-1; start<end; start++, end--)
     {
        if (number[start]!=number[end])
            return false;
     }
    return true;
}

int main ()
{
    Pallindrome num(809);   // <- This Does
    //Digitize numb(809);   // <- This Does Not Give an Error
    //num.ispallindrome() ? cout << "True" << endl : cout<< "False" << endl;
    //num.Display();
    return 0;
}

[NathanOliver]

You are calling delete on number in your destructor for your palindorme class. You shouldnt do that. All members of the base class should be taken care of in the base class destructor like you have on line 13.

[mike_2000_17]

And, you should make the base-class desctructor virtual, as so:

class Digitize
{
 protected:
    int * number;
    int Digits;
 public:
    Digitize(_uint64);
    virtual ~Digitize() {delete [] number;} // notice the 'virtual' here.
    void Display();
};