-
Notifications
You must be signed in to change notification settings - Fork 0
/
closest_nodes.go
51 lines (42 loc) · 1018 Bytes
/
closest_nodes.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
package dht
import (
"container/heap"
)
type nodeMaxHeap struct {
IDs []nodeID
Target nodeID
}
func (me nodeMaxHeap) Len() int { return len(me.IDs) }
func (me nodeMaxHeap) Less(i, j int) bool {
m := me.IDs[i].Distance(&me.Target)
n := me.IDs[j].Distance(&me.Target)
return m.Cmp(&n) > 0
}
func (me *nodeMaxHeap) Pop() (ret interface{}) {
ret, me.IDs = me.IDs[len(me.IDs)-1], me.IDs[:len(me.IDs)-1]
return
}
func (me *nodeMaxHeap) Push(val interface{}) {
me.IDs = append(me.IDs, val.(nodeID))
}
func (me nodeMaxHeap) Swap(i, j int) {
me.IDs[i], me.IDs[j] = me.IDs[j], me.IDs[i]
}
type closestNodesSelector struct {
closest nodeMaxHeap
k int
}
func (me *closestNodesSelector) Push(id nodeID) {
heap.Push(&me.closest, id)
if me.closest.Len() > me.k {
heap.Pop(&me.closest)
}
}
func (me *closestNodesSelector) IDs() []nodeID {
return me.closest.IDs
}
func newKClosestNodesSelector(k int, targetID nodeID) (ret closestNodesSelector) {
ret.k = k
ret.closest.Target = targetID
return
}