1 ! Copyright (C) 2007, 2008 Ryan Murphy, Doug Coleman,
3 ! See http://factorcode.org/license.txt for BSD license.
4 USING: accessors arrays assocs fry kernel kernel.private locals
5 math math.order math.private sequences sequences.private summary
9 GENERIC: heap-push* ( value key heap -- entry )
10 GENERIC: heap-peek ( heap -- value key )
11 GENERIC: heap-pop* ( heap -- )
12 GENERIC: heap-delete ( entry heap -- )
13 GENERIC: heap-empty? ( heap -- ? )
14 GENERIC: heap-size ( heap -- n )
18 TUPLE: heap { data vector } ;
20 : <heap> ( class -- heap )
21 V{ } clone swap boa ; inline
23 TUPLE: entry value key heap index ;
25 : <entry> ( value key heap -- entry )
30 TUPLE: min-heap < heap ;
32 : <min-heap> ( -- min-heap ) min-heap <heap> ;
34 TUPLE: max-heap < heap ;
36 : <max-heap> ( -- max-heap ) max-heap <heap> ;
38 M: heap heap-empty? ( heap -- ? )
39 data>> empty? ; inline
41 M: heap heap-size ( heap -- n )
42 data>> length ; inline
47 { fixnum } declare 1 fixnum-shift-fast 1 fixnum+fast ; inline
50 { fixnum } declare 1 fixnum-shift-fast 2 fixnum+fast ; inline
53 { fixnum } declare 1 fixnum-fast 2/ ; inline
55 : data-nth ( n data -- entry )
56 nth-unsafe { entry } declare ; inline
58 : data-set-nth ( entry n data -- )
59 [ [ >>index ] keep ] dip set-nth-unsafe ; inline
61 : data-push ( entry data -- n )
62 [ length [ >>index ] keep ]
63 [ [ set-nth ] keepd ] bi ; inline
65 GENERIC: heap-compare ( entry1 entry2 heap -- ? )
67 M: min-heap heap-compare
68 drop { entry entry } declare [ key>> ] bi@ after? ; inline
70 M: max-heap heap-compare
71 drop { entry entry } declare [ key>> ] bi@ before? ; inline
73 : (heapdata-compare) ( m n data heap -- ? )
74 [ '[ _ data-nth ] bi@ ] [ heap-compare ] bi* ; inline
76 : heapdata-compare ( m n heap -- ? )
77 [ data>> ] keep (heapdata-compare) ; inline
81 : >entry< ( entry -- value key )
82 [ value>> ] [ key>> ] bi ; inline
84 M: heap heap-peek ( heap -- value key )
85 data>> first >entry< ;
89 :: sift-down ( heap from to -- )
91 to data data-nth :> tmp
93 to t [ over from > and ] [
96 dup tmp heap heap-compare [
97 rot data data-set-nth t
103 tmp swap data data-set-nth ; inline
108 [ <entry> dup ] [ data>> data-push ] [ 0 rot sift-down ] tri ;
110 : heap-push ( value key heap -- )
113 : heap-push-all ( assoc heap -- )
114 '[ swap _ heap-push ] assoc-each ;
118 :: sift-up ( heap n -- )
121 n data data-nth :> tmp
123 n dup left [ dup end < ] [
126 2dup data heap (heapdata-compare)
129 [ data data-nth swap data data-set-nth ]
133 tmp over data data-set-nth
134 heap n rot sift-down ; inline
139 dup data>> dup length 1 > [
140 [ first f >>index drop ] [ pop ] [ set-first ] tri 0 sift-up
145 : heap-pop ( heap -- value key )
146 [ heap-peek ] [ heap-pop* ] bi ;
148 : slurp-heap ( ... heap quot: ( ... value key -- ... ) -- ... )
149 [ drop '[ _ heap-empty? ] ]
150 [ '[ _ heap-pop @ ] until ] 2bi ; inline
152 : heap-pop-all ( heap -- alist )
153 [ heap-size <vector> ] keep
154 [ swap 2array suffix! ] slurp-heap { } like ;
156 ERROR: bad-heap-delete ;
158 M: bad-heap-delete summary
159 drop "Invalid entry passed to heap-delete" ;
163 : entry>index ( entry heap -- n )
164 over heap>> eq? [ bad-heap-delete ] unless
165 index>> dup [ bad-heap-delete ] unless
166 { fixnum } declare ; inline
171 [ entry>index ] [ f rot index<< ] 2bi
172 2dup heap-size 1 - = [
176 [ data>> data-set-nth ]
177 [ swap sift-up ] 2tri
180 : >min-heap ( assoc -- min-heap )
181 dup assoc-size <vector> min-heap boa
182 [ heap-push-all ] keep ;
184 : >max-heap ( assoc -- max-heap )
185 dup assoc-size <vector> max-heap boa
186 [ heap-push-all ] keep ;