Programming

I am trying to implement a spare array in C that would be referenced by regular integers.
Right away: define array for maximum possible index elements completely is not what I trying to get!!!

It should be a construction that would have just 2 elements if I need to have just two indexes, like 2000 and 5, let say.

(Genarally, as a hash in perl, for example)
If I need to have that indexed by strings or characters, the 'enum' allows to nicely prepare that.

But with integers it is not compiled.
I mean no way to define

Code:

  enum E_TYPE {1,4,2};

By usage my intention is to have a way to work with an array of numbers referencing to elements by another set of numbers, that could be not consecuensed, not from 0 and without using the search by any way (loop, or any other smartness)

So, I would have related info-array, say, like this:

Code:

struct {int key; int val;} Inf_Arr[] = {
   {25, 44},
   {35, 55},
   (1,  99} };

And I would like to get Int_Arr[n].val by some Ref_Arr[ Int_Arr[n].key ]

So, having int a = Ref_Arr[25]; - I would have a==44

One again, I would like to construct data in a way to be able access the 'val' by the 'key' and (!!) - without using a 'switch-case', if, or any loop for each single 'key' through whole Inf_Arr[]

Does anybody know how it could be done?
Any idea?