I have this example of using a copy constructer with a class that dynamically allocates memory.
#include<iostream>
#include<vector>
using namespace std;
class CTest
{
public:
CTest() { pVal = new int; *pVal = 10;}
CTest(CTest &c) {pVal = new int; *pVal = *c.pVal;} //copy constructer
~CTest() {delete pVal;}
int * pVal;
};
int main()
{
CTest c;
cout << *c.pVal<<"\n";
*c.pVal = 50;
CTest a = c;
*c.pVal = 40;
cout << *a.pVal<<"\n";
cout << *c.pVal<<"\n";
return 0;
}
That works fine
But when I try to create a vector of CTest’s and use it to initialize another vector it wont compile. If I don’t define a copy constructor and use the compiler default then it works fine. So I think the STL wants a me to overload the copy constructor other then
CTest::CTest( CTest & c);
But I don’t know what it is
Here’s the code that wont work
#include<iostream>
#include<vector>
using namespace std;
class CTest
{
public:
CTest() { pVal = new int; *pVal = 10;}
CTest(int v){ pVal = new int; *pVal = v;}
CTest(CTest &c) {pVal = new int; *pVal = *c.pVal;} // copy constructer
~CTest() {delete pVal;}
int * pVal;
};
int main()
{
vector <CTest> v1;
for (int i=0; i<10; i++)
v1.push_back(CTest(i));
vector <CTest> v2 = v1;
return 0;
}
