Question

I have a method in a class LinkRepository, I am checking for duplicate entries in the vector array Datalinks, which is a member of the class. I loop through all the elements in the array to check in the new entry Datalink* datalink already exist in the array. If so then don’t add, just exit the loop.

void LinkRepository::SaveLink(Datalink* datalink) {
bool Exist = false;

for(vector<Datalink*>::iterator dl = Datalinks.begin(); dl != Datalinks.end(); ++dl)
{
     if((strstr((*dl)->ParentID, datalink->ParentID) != NULL) && (strstr((*dl)->ChildID,datalink->ChildID) != NULL))
     {
          Exist = true;

          dl = Datalinks.end();
     }
}

    if(!Exist)
    {
        Datalinks.push_back(datalink);
    }
};

My program seems to crash on the next loop of the statement dl = Datalinks.end();

I have no idea why it is crashing?

Answer 1

Replace

dl = Datalinks.end();

With:

break;

To exit the loop

Here is a simple example to illustrate why your solution can’t work:

int i = 0;
for (; i != 10; ++i)
{
    i = 10;
}

This loop will never end because i will be incremented to 11 before comparison i != 10