summaryrefslogtreecommitdiffstats
path: root/kpat/freecell-solver/pqueue.c
diff options
context:
space:
mode:
authortoma <toma@283d02a7-25f6-0310-bc7c-ecb5cbfe19da>2009-11-25 17:56:58 +0000
committertoma <toma@283d02a7-25f6-0310-bc7c-ecb5cbfe19da>2009-11-25 17:56:58 +0000
commitc90c389a8a8d9d8661e9772ec4144c5cf2039f23 (patch)
tree6d8391395bce9eaea4ad78958617edb20c6a7573 /kpat/freecell-solver/pqueue.c
downloadtdegames-c90c389a8a8d9d8661e9772ec4144c5cf2039f23.tar.gz
tdegames-c90c389a8a8d9d8661e9772ec4144c5cf2039f23.zip
Copy the KDE 3.5 branch to branches/trinity for new KDE 3.5 features.
BUG:215923 git-svn-id: svn://anonsvn.kde.org/home/kde/branches/trinity/kdegames@1054174 283d02a7-25f6-0310-bc7c-ecb5cbfe19da
Diffstat (limited to 'kpat/freecell-solver/pqueue.c')
-rw-r--r--kpat/freecell-solver/pqueue.c173
1 files changed, 173 insertions, 0 deletions
diff --git a/kpat/freecell-solver/pqueue.c b/kpat/freecell-solver/pqueue.c
new file mode 100644
index 00000000..086cce96
--- /dev/null
+++ b/kpat/freecell-solver/pqueue.c
@@ -0,0 +1,173 @@
+/*
+ pqueue.c - implementation of a priority queue by using a binary heap.
+
+ Originally written by Justin-Heyes Jones
+ Modified by Shlomi Fish, 2000
+
+ This file is in the public domain (it's uncopyrighted).
+
+ Check out Justin-Heyes Jones' A* page from which this code has
+ originated:
+ http://www.geocities.com/jheyesjones/astar.html
+ */
+
+/* manage a priority queue as a heap
+ the heap is implemented as a fixed size array of pointers to your data */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "jhjtypes.h"
+
+#include "pqueue.h"
+
+#ifdef DMALLOC
+#include "dmalloc.h"
+#endif
+
+#define TRUE 1
+#define FALSE 0
+
+/* initialise the priority queue with a maximum size of maxelements. maxrating is the highest or lowest value of an
+ entry in the pqueue depending on whether it is ascending or descending respectively. Finally the bool32 tells you whether
+ the list is sorted ascending or descending... */
+
+void freecell_solver_PQueueInitialise(
+ PQUEUE *pq,
+ int32 MaxElements
+ )
+{
+ pq->MaxSize = MaxElements;
+
+ pq->CurrentSize = 0;
+
+ pq->Elements = (pq_element_t*) malloc( sizeof( pq_element_t ) * (MaxElements + 1) );
+
+ if( pq->Elements == NULL )
+ {
+ printf( "Memory alloc failed!\n" );
+ }
+}
+
+/* join a priority queue
+ returns TRUE if successful, FALSE if fails. (You fail by filling the pqueue.)
+ PGetRating is a function which returns the rating of the item you're adding for sorting purposes */
+
+int freecell_solver_PQueuePush( PQUEUE *pq, void *item, pq_rating_t r)
+{
+ uint32 i;
+ pq_element_t * Elements = pq->Elements;
+
+ int32 CurrentSize = pq->CurrentSize;
+
+ if (CurrentSize == pq->MaxSize )
+ {
+ int new_size;
+ new_size = pq->MaxSize + 256;
+ pq->Elements = Elements = (pq_element_t *)realloc( Elements, sizeof(pq_element_t) * (new_size+1));
+ pq->MaxSize = new_size;
+ }
+
+ {
+ /* set i to the first unused element and increment CurrentSize */
+
+ i = (++CurrentSize);
+
+ /* while the parent of the space we're putting the new node into is worse than
+ our new node, swap the space with the worse node. We keep doing that until we
+ get to a worse node or until we get to the top
+
+ note that we also can sort so that the minimum elements bubble up so we need to loops
+ with the comparison operator flipped... */
+
+ {
+
+ while( ( i==PQ_FIRST_ENTRY ?
+ (PQUEUE_MaxRating) /* return biggest possible rating if first element */
+ :
+ (PGetRating(Elements[ PQ_PARENT_INDEX(i) ]) )
+ )
+ < r
+ )
+ {
+ Elements[ i ] = Elements[ PQ_PARENT_INDEX(i) ];
+
+ i = PQ_PARENT_INDEX(i);
+ }
+ }
+
+ /* then add the element at the space we created. */
+ Elements[i].item = item;
+ Elements[i].rating = r;
+ }
+
+ pq->CurrentSize = CurrentSize;
+
+ return TRUE;
+
+}
+
+#define PQueueIsEmpty(pq) ((pq)->CurrentSize == 0)
+
+/* free up memory for pqueue */
+void freecell_solver_PQueueFree( PQUEUE *pq )
+{
+ free( pq->Elements );
+}
+
+/* remove the first node from the pqueue and provide a pointer to it */
+
+void *freecell_solver_PQueuePop( PQUEUE *pq)
+{
+ int32 i;
+ int32 child;
+ pq_element_t * Elements = pq->Elements;
+ int32 CurrentSize = pq->CurrentSize;
+
+ pq_element_t pMaxElement;
+ pq_element_t pLastElement;
+
+ if( PQueueIsEmpty( pq ) )
+ {
+ return NULL;
+ }
+
+ pMaxElement = Elements[PQ_FIRST_ENTRY];
+
+ /* get pointer to last element in tree */
+ pLastElement = Elements[ CurrentSize-- ];
+
+ {
+
+ /* code to pop an element from an ascending (top to bottom) pqueue */
+
+ /* UNTESTED */
+
+ for( i=PQ_FIRST_ENTRY; (child = PQ_LEFT_CHILD_INDEX(i)) <= CurrentSize; i=child )
+ {
+ /* set child to the smaller of the two children... */
+
+ if( (child != CurrentSize) &&
+ (PGetRating(Elements[child + 1]) > PGetRating(Elements[child])) )
+ {
+ child ++;
+ }
+
+ if( PGetRating( pLastElement ) < PGetRating( Elements[ child ] ) )
+ {
+ Elements[ i ] = Elements[ child ];
+ }
+ else
+ {
+ break;
+ }
+ }
+ }
+
+ Elements[i] = pLastElement;
+ pq->CurrentSize = CurrentSize;
+
+ return pMaxElement.item;
+}
+
+