hello-algo/codes/go/chapter_graph/graph_adjacency_list.go
krahets 0bec52d7cc Polish the chapter of heap, introduction, preface.
Replace "其它" with "其他"
2023-04-09 19:12:37 +08:00

100 lines
2.2 KiB
Go
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

// File: graph_adjacency_list.go
// Created Time: 2023-01-31
// Author: Reanon (793584285@qq.com)
package chapter_graph
import (
"fmt"
"strconv"
"strings"
. "github.com/krahets/hello-algo/pkg"
)
/* 基于邻接表实现的无向图类 */
type graphAdjList struct {
// 邻接表key: 顶点value该顶点的所有邻接顶点
adjList map[Vertex][]Vertex
}
/* 构造方法 */
func newGraphAdjList(edges [][]Vertex) *graphAdjList {
g := &graphAdjList{
adjList: make(map[Vertex][]Vertex),
}
// 添加所有顶点和边
for _, edge := range edges {
g.addVertex(edge[0])
g.addVertex(edge[1])
g.addEdge(edge[0], edge[1])
}
return g
}
/* 获取顶点数量 */
func (g *graphAdjList) size() int {
return len(g.adjList)
}
/* 添加边 */
func (g *graphAdjList) addEdge(vet1 Vertex, vet2 Vertex) {
_, ok1 := g.adjList[vet1]
_, ok2 := g.adjList[vet2]
if !ok1 || !ok2 || vet1 == vet2 {
panic("error")
}
// 添加边 vet1 - vet2, 添加匿名 struct{},
g.adjList[vet1] = append(g.adjList[vet1], vet2)
g.adjList[vet2] = append(g.adjList[vet2], vet1)
}
/* 删除边 */
func (g *graphAdjList) removeEdge(vet1 Vertex, vet2 Vertex) {
_, ok1 := g.adjList[vet1]
_, ok2 := g.adjList[vet2]
if !ok1 || !ok2 || vet1 == vet2 {
panic("error")
}
// 删除边 vet1 - vet2
DeleteSliceElms(g.adjList[vet1], vet2)
DeleteSliceElms(g.adjList[vet2], vet1)
}
/* 添加顶点 */
func (g *graphAdjList) addVertex(vet Vertex) {
_, ok := g.adjList[vet]
if ok {
return
}
// 在邻接表中添加一个新链表
g.adjList[vet] = make([]Vertex, 0)
}
/* 删除顶点 */
func (g *graphAdjList) removeVertex(vet Vertex) {
_, ok := g.adjList[vet]
if !ok {
panic("error")
}
// 在邻接表中删除顶点 vet 对应的链表
delete(g.adjList, vet)
// 遍历其他顶点的链表,删除所有包含 vet 的边
for _, list := range g.adjList {
DeleteSliceElms(list, vet)
}
}
/* 打印邻接表 */
func (g *graphAdjList) print() {
var builder strings.Builder
fmt.Printf("邻接表 = \n")
for k, v := range g.adjList {
builder.WriteString("\t\t" + strconv.Itoa(k.Val) + ": ")
for _, vet := range v {
builder.WriteString(strconv.Itoa(vet.Val) + " ")
}
fmt.Println(builder.String())
builder.Reset()
}
}