Help with setting all elements of array to 0

[rex1200]

Hi,

I'm trying to set all the elements of my array to 0 but nothing seems to be working. Could greatly use some help. Thanks!



.h

#ifndef ServerGroup_h
#define ServerGroup_h

class ServerGroup 
{
  
public:
  ServerGroup(const int&); 

private:
  int *servers;

};

#endif  

.cpp

ServerGroup::ServerGroup(const int& numArray) 
{
  size = numArray; // number of elements in the array
  

  servers = new int [numArray]; // pointer to numArray
  size = numArray; // size = elements in the array

}

I want to set each element of the array in servers to 0 based on what is passed into size by numArray.

[LB]

Lines 3 and 7 do the same thing in your cpp code, and where is size defined in your header?

[Cubbi]

both vector<int>(numArray) and new int[numArray]() will set them all to zero. Any specific reason you want to use new[] instead of a vector?

[rex1200]

Thanks and we can't use vector yet because our textbook hasn't covered vectors yet. We have only just been introduced to "new". Ah and yes sorry about lines 3 and 7 being the same. I was playing around with my code and didn't realize I copied and pasted something twice in different places. Good eye!

[rex1200]

Would new int[numArray]() be doing the same thing as this for loop?

Basically I just want to set servers to 0.

ServerGroup::ServerGroup(const int& numArray) // set # elements in dynamic array
{
  servers = new int[numArray];
  size = numArray;
  for(int i = 0; i < size; i++)
  {
    servers[i]=0;
  }
}

vs

ServerGroup::ServerGroup(const int& numArray) // set # elements in dynamic array
{
  size = numArray; // num elements in array
  servers = new int [numArray](); 
}

[Cubbi]

yes, servers = new int[numArray](); sets all servers to 0. It's when you need initial values other than zero when you need a loop (or, more typically, a vector)

[rex1200]

Thanks! So in this case the easier and cleaner code would be to simply use servers = new int [numArray](); then?

I'll use that over the for loop. Thanks

[LB]

The easier and cleaner code involves using std::vector ;)

[cbretana]

well, in the case of you're using a simple array, you can use the fill function contained in the algorithm library, or simply you can use the iterator method -- for(i = 1 -- N) arr[i] = 0, you can create a new instance of the array, or you can use the data structure vector<Object>

the structure of fill is just like this:
fill(array+1, array+N+1, 0);

regards and good luck ;)

[LB]

cbretana wrote:

the structure of fill is just like this:
fill(array+1, array+N+1, 0);

Where did you come up with this? This will not only skip the first element in the array but also corrupt memory after the array.