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graph/simple: separate weighted and unweighted edge implementations

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This commit is contained in:
kortschak
2017-08-22 15:53:09 +09:30
parent 7ba61f0ead
commit f739fbf133
27 changed files with 192 additions and 181 deletions
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16
graph/path/spanning_tree.go
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@@ -27,10 +27,10 @@ func Prim(dst graph.UndirectedBuilder, g graph.WeightedUndirected) float64 {
q := &primQueue{
indexOf: make(map[int64]int, len(nodes)-1),
nodes: make([]simple.Edge, 0, len(nodes)-1),
nodes: make([]simple.WeightedEdge, 0, len(nodes)-1),
}
for _, u := range nodes[1:] {
heap.Push(q, simple.Edge{F: u, W: math.Inf(1)})
heap.Push(q, simple.WeightedEdge{F: u, W: math.Inf(1)})
}
u := nodes[0]
@@ -44,7 +44,7 @@ func Prim(dst graph.UndirectedBuilder, g graph.WeightedUndirected) float64 {
var w float64
for q.Len() > 0 {
e := heap.Pop(q).(simple.Edge)
e := heap.Pop(q).(simple.WeightedEdge)
if e.To() != nil && g.HasEdgeBetween(e.From(), e.To()) {
dst.SetEdge(e)
w += e.Weight()
@@ -72,7 +72,7 @@ func Prim(dst graph.UndirectedBuilder, g graph.WeightedUndirected) float64 {
// spanning forest.
type primQueue struct {
indexOf map[int64]int
nodes []simple.Edge
nodes []simple.WeightedEdge
}
func (q *primQueue) Less(i, j int) bool {
@@ -90,7 +90,7 @@ func (q *primQueue) Len() int {
}
func (q *primQueue) Push(x interface{}) {
n := x.(simple.Edge)
n := x.(simple.WeightedEdge)
q.indexOf[n.From().ID()] = len(q.nodes)
q.nodes = append(q.nodes, n)
}
@@ -141,7 +141,7 @@ type UndirectedWeightLister interface {
// spanning tree weights will be returned.
func Kruskal(dst graph.UndirectedBuilder, g UndirectedWeightLister) float64 {
edges := g.Edges()
ascend := make([]simple.Edge, 0, len(edges))
ascend := make([]simple.WeightedEdge, 0, len(edges))
for _, e := range edges {
u := e.From()
v := e.To()
@@ -149,7 +149,7 @@ func Kruskal(dst graph.UndirectedBuilder, g UndirectedWeightLister) float64 {
if !ok {
panic("kruskal: unexpected invalid weight")
}
ascend = append(ascend, simple.Edge{F: u, T: v, W: w})
ascend = append(ascend, simple.WeightedEdge{F: u, T: v, W: w})
}
sort.Sort(byWeight(ascend))
@@ -169,7 +169,7 @@ func Kruskal(dst graph.UndirectedBuilder, g UndirectedWeightLister) float64 {
return w
}
type byWeight []simple.Edge
type byWeight []simple.WeightedEdge
func (e byWeight) Len() int { return len(e) }
func (e byWeight) Less(i, j int) bool { return e[i].Weight() < e[j].Weight() }