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
75 : >entry< ( entry -- value key )
76 [ value>> ] [ key>> ] bi ; inline
78 M: heap heap-peek ( heap -- value key )
79 data>> first >entry< ;
83 :: sift-down ( heap from to -- )
85 to data data-nth :> tmp
87 to t [ over from > and ] [
90 dup tmp heap heap-compare [
91 rot data data-set-nth t
97 tmp swap data data-set-nth ; inline
102 [ <entry> dup ] [ data>> data-push ] [ 0 rot sift-down ] tri ;
104 : heap-push ( value key heap -- )
107 : heap-push-all ( assoc heap -- )
108 '[ swap _ heap-push ] assoc-each ;
112 :: sift-up ( heap n -- )
115 n data data-nth :> tmp
117 n dup left [ dup end < ] [
120 2dup [ data data-nth ] bi@ heap heap-compare
123 [ data data-nth swap data data-set-nth ]
127 tmp over data data-set-nth
128 heap n rot sift-down ; inline
133 dup data>> dup length 1 > [
134 [ first f >>index drop ] [ pop ] [ set-first ] tri 0 sift-up
139 : heap-pop ( heap -- value key )
140 [ heap-peek ] [ heap-pop* ] bi ;
142 : slurp-heap ( ... heap quot: ( ... value key -- ... ) -- ... )
143 [ drop '[ _ heap-empty? ] ]
144 [ '[ _ heap-pop @ ] until ] 2bi ; inline
146 : heap-pop-all ( heap -- alist )
147 [ heap-size <vector> ] keep
148 [ swap 2array suffix! ] slurp-heap { } like ;
150 ERROR: bad-heap-delete ;
152 M: bad-heap-delete summary
153 drop "Invalid entry passed to heap-delete" ;
157 : entry>index ( entry heap -- n )
158 over heap>> eq? [ bad-heap-delete ] unless
159 index>> dup [ bad-heap-delete ] unless
160 { fixnum } declare ; inline
165 [ entry>index ] [ f rot index<< ] 2bi
166 2dup heap-size 1 - = [
170 [ data>> data-set-nth ]
171 [ swap sift-up ] 2tri
174 : >min-heap ( assoc -- min-heap )
175 dup assoc-size <vector> min-heap boa
176 [ heap-push-all ] keep ;
178 : >max-heap ( assoc -- max-heap )
179 dup assoc-size <vector> max-heap boa
180 [ heap-push-all ] keep ;