Geek Answers Handbook

C ++ destructor deletes shared memory

I have a C ++ program that does the following: get an unsorted array of integers and divide it into subarrays in ascending order. eg. my array is 1,2,3, -2,4 Thus, the output will be: 1,2,3 // sub array 1 -2,4 // sub array 2

the way I demanded to do this is to allocate an array of pointers, and each cell in this array will point to an additional array (also dynamic) containing one series. Also, I am not allowed to change the "main" function

I now have a "print" method that prints subarrays using operator overloading.

I checked and found that the printing method worked fine, but in this piece of code:

cout << "\ns3: \n";
  print(s3);

  s3 = s1;
  cout << "\ns3 again: \n";
  print(s3);

print (s3) prints fine, but after the assignment statement when I call print (s3) again, I get the output file. after some dubugging, I think it came out to the destructor something.

I really understand this if someone can point out and identify my problem and come up with a solution. of course i will give the source code

Update

I want to explain myself a little better: after each call to "print", when I trace, the first thing that is done before the "print" is the copy constructor. when I set a breakpoint in the copy constructor, I see that the "src" pointer in the function signature (copy constructor function) points to the correct location (the first element in the array), but after assigning s3 = s1, when I print (s3) again pointer in copy constructor is undesirable

**

here is the code:

   // HW4.cpp : Defines the entry point for the console application.
//

#include <iostream>
using namespace std;


//global declerations and indexes//
typedef long int * LONG_INT_PTR;        

//class     
class SeriesArray
{
//members declerations
private: 
        LONG_INT_PTR *stable;
        int *count_arr;   //help array that indicate how many serieses made from the array and how many element in each series
        int count_size;   //  help counter
        int size;

public:
        SeriesArray::SeriesArray(LONG_INT_PTR arr, int n );
        SeriesArray::SeriesArray(const SeriesArray& src );
        SeriesArray::~SeriesArray();
        long int SeriesArray::get_entry(int i,int j) const;
        SeriesArray& SeriesArray::operator=(const SeriesArray& src);
        friend ostream& operator<<(ostream& stream, const SeriesArray& src);//global - not member
};


//members implementation
        //default constructor
        SeriesArray::SeriesArray(LONG_INT_PTR arr, int n )
        {
            size=n;
            int j=0;
            int s=0;
            count_size=0;
            count_arr=new int[size];
            for (int i=0;i<size;i++)
            {
                if (arr[i]<arr[i+1])
                    count_size++;
                else
                {
                    count_size++;
                    count_arr[j]=count_size;
                    j++;
                    count_size=0;
                }
            }
            size=j;
            stable=new LONG_INT_PTR[size];
            for (int i=0;i<size;i++)
            {
                stable[i]=new long int[count_arr[i]];
                for (int k=0;k<count_arr[i];k++)
                {
                    stable[i][k]=arr[s];
                    s++;
                }
            }

    }

    //copy constructor
    SeriesArray::SeriesArray(const SeriesArray& src )
    {

            size=src.size;
            count_arr=new int[size];
            stable=new LONG_INT_PTR[size];
            for (int i=0;i<size;i++)
            {
                count_arr[i]=src.count_arr[i];
                stable[i]=new long int[count_arr[i]];
            }
            memcpy(this->stable,src.stable,src.size*sizeof(long int));
    }

    //destructor
    SeriesArray::~SeriesArray()
    {
        for (int i=0;i<size;++i)
                delete[] stable[i];
        delete[] this->count_arr;
        count_size=0;
    }

    //member
    long int SeriesArray::get_entry(int i,int j) const
    {

        if (i<this->count_size&&this->stable[i][j]!=NULL)
            return (this->stable[i][j]);
        else return NULL;
    }


    //overload = operator
    SeriesArray& SeriesArray::operator=(const SeriesArray& src)
    {
        if (this==&src)
          return *this;

        if (stable!=NULL)
            delete[] stable;
        if (count_arr!=NULL)
            delete[] count_arr;
            //for (int i=0;i<size;i++)
            //  delete[] stable[i];
            size=src.size;
            count_arr=new int[src.size];
            memcpy(count_arr,src.count_arr,src.size*sizeof(int));
            stable=new LONG_INT_PTR[size];
            for (int i=0;i<size;i++)
            {
            //  count_arr[i]=rhs.count_arr[i];
                stable[i]=new long int[src.count_arr[i]];
            }
            memcpy(stable,src.stable,src.size*sizeof(long int));

        return *this;
    }


//***************************************************************************************************************************************************//
//global//

    //overload operator <<
    ostream& operator<<(ostream& stream,const SeriesArray& src)
    {
        for (int i=0;i<src.size;i++)
        {
        for (int j=0;j<src.count_arr[i];j++)
         {
            stream << " " << src.stable[i][j] << " " ; 
         }
        stream << "\n\n\n" ;
     }

        return stream;
    }

    //print
    void print(SeriesArray src)
    {
         cout << src;
        cout << "\n";
    }  // print



//main  
int main()
{
  long int arr1[20] = {23, 91, -71, -63, 22,  55, 51, 73, 17, -19,
                      -65, 44, 95,  66, 82, 85, 97, 30, 54, -34};
  long int arr2[10] = {0, 1, -7, -6, 2,  5, 6, 7, 1, -1};

  int count[20], i, j, n =20, sno;

  long int *parr[20];

  SeriesArray s1(arr1, 20);
  SeriesArray s2(arr2, 10);
  SeriesArray s3(arr2, 10);


  cout << "\narr1:\n";

  for(i=0; i < 20; i++)
    cout <<  "  " << arr1[i] << "  ";
  cout << "\n";

  cout << "\n\ntable:\n";
  print(s1); 

  cout << "\narr2\n";

  for(i=0; i < 10; i++)
    cout <<  "  " << arr2[i] << "  ";
  cout << "\n";

  cout << "\n\ntable:\n";
  print(s2);

  cout << "\ns3: \n";
  print(s3);


  s3 = s1;
  cout << "\ns3 again: \n";
  print(s3);

  cout << "\ns1 again: \n";
  print(s1);

  cin>>i;
 return 0;
} // main
+4
3

, , .

        for (int i=0;i<size;i++)
        {
        //  count_arr[i]=rhs.count_arr[i];
            stable[i]=new long int[src.count_arr[i]];
        }
        memcpy(stable,src.stable,src.size*sizeof(long int));

,

        for (int i = 0; i < size; i++)
        {
            stable[i] = new long int[src.count_arr[i]];
            memcpy(stable[i], src.stable[i], src.count_arr[i]*sizeof(long int));
        }


SeriesArray::SeriesArray(const SeriesArray& src )
{

        size=src.size;
        count_arr=new int[size];
        stable=new LONG_INT_PTR[size];
        for (int i=0;i<size;i++)
        {
            count_arr[i]=src.count_arr[i];
            stable[i]=new long int[count_arr[i]];
        }
        memcpy(this->stable,src.stable,src.size*sizeof(long int));
}


SeriesArray::SeriesArray(const SeriesArray& src )
{

        size=src.size;
        count_arr=new int[size];
        stable=new LONG_INT_PTR[size];
        for (int i=0;i<size;i++)
        {
            count_arr[i]=src.count_arr[i];
            stable[i]=new long int[count_arr[i]];
            memcpy(stable[i], src.stable[i], src.count_arr[i]*sizeof(long int));
        }
}

, , 2D-.

+2

stable, memcpy.

( vector .)

, print const, .

+1

, , ( gcc ).

void print(SeriesArray src)

. print ( ). , src ( ). , . , = .

void print(SeriesArray & src)

Then there is an invalid pointer, as you already read in my comment. In addition, you do not allocate enough space for stability. You should rewrite your constructor this way - or in a more elegant way if you want ...

SeriesArray::SeriesArray(LONG_INT_PTR arr, int n )
{
    size=n;
    int j=0;
    int s=0;
    count_size=1;
    count_arr=new int[size];
    for (int i=0;i<size-1;i++)
    {
        if (arr[i]<arr[i+1])
            count_size++;
        else
        {
            count_arr[j]=count_size;
            j++;
            count_arr[j]=1;
            count_size=1;
        }
    }
    size=j+1;
    stable=new LONG_INT_PTR[size];
    for (int i=0;i<size;i++)
    {
        stable[i]=new long int[count_arr[i]];
        for (int k=0;k<count_arr[i];k++)
        {
            stable[i][k]=arr[s];
            s++;
        }
    }
}
0
source

More articles:


All Articles