The Vheap structure. More...
|
Functions | |
| Vheap * | elektraVheapInit (VheapComp comp, size_t minSize) |
| Allocates vheap with size specified by parameter minSize. More... | |
| int | elektraVheapIsEmpty (const Vheap *vheap) |
| Checks if the heap is empty. More... | |
| void | elektraVheapDel (Vheap *vheap) |
| Deletes the heap, by freeing all the memory. | |
| int | elektraVheapInsert (Vheap *vheap, void *data) |
| Inserts an element in the Vheap, by finding the right position. More... | |
| void * | elektraVheapRemove (Vheap *vheap) |
| Removes and returns an element from the Vheap, by taking the first element which is ordered by VheapComp, after removal the remaining elements get ordered again. More... | |
| int | elektraVheapClear (Vheap *vheap) |
| Clears the heap in a fast fashion. More... | |
Detailed Description
The Vheap structure.
A heap is a Data structure which keeps the data ordered. Elements can only be retrieved in this order! Insertions and retrieves need log (n).
This implementation allocates memory dynamically. The space gets doubled if full and reduced by half if used only a quarter of it, but not less than minSize.
To construct a max heap the comparison function VheapComp (a, b), must return 1 on a > b and 0 otherwise. For a min heap 1 on a < b and 0 otherwise.
Function Documentation
| int elektraVheapClear | ( | Vheap * | vheap | ) |
Clears the heap in a fast fashion.
Set the count to zero and does not reallocate memory. The next reallocation happens at Remove.
- Return values
-
1 on success 0 on error
| Vheap* elektraVheapInit | ( | VheapComp | comp, |
| size_t | minSize | ||
| ) |
Allocates vheap with size specified by parameter minSize.
To construct a max heap the comparison function VheapComp (a, b), must return 1 on a > b and 0 otherwise. For a min heap 1 on a < b and 0 otherwise.
- Parameters
-
comp the comparison function of the heap minSize the minimum size of the heap
- Return values
-
a Vheap pointer NULL error
| int elektraVheapInsert | ( | Vheap * | vheap, |
| void * | data | ||
| ) |
Inserts an element in the Vheap, by finding the right position.
Resizes the memory first if needed.
- Parameters
-
data the element
- Return values
-
0 on error 1 otherwise
| int elektraVheapIsEmpty | ( | const Vheap * | vheap | ) |
Checks if the heap is empty.
- Return values
-
1 on empty 0 on non empty -1 on error
| void* elektraVheapRemove | ( | Vheap * | vheap | ) |
Removes and returns an element from the Vheap, by taking the first element which is ordered by VheapComp, after removal the remaining elements get ordered again.
Resizes the heap if needed.
- Return values
-
the element NULL on error
